Vienna Convention on the Law of Treaties between States and International Organisations and between International Organisations (1986)

Vienna Convention on the Law of Treaties between States and International Organizations or between International Organizations Done at Vienna on 21 March 1986

The Parties to the present Convention,

Considering the fundamental role of treaties in the history of international relations,

Recognizing the consensual nature of treaties and their ever-increasing importance as a source of international law,

Noting that the principles of free consent and of good faith and the pacta sunt servanda rule are universally recognized,

Affirming the importance of enhancing the process of codification and progressive development of international law at a universal level,

Believing that the codification and progressive development of the rules relating to treaties between States and international organizations or between international organizations are means of enhancing legal order in international relations and of serving the purposes of the United Nations,

Having in mind the principles of international law embodied in the Charter of the United Nations, such as the principles of the equal rights and self-determination of peoples, of the sovereign equality and independence of all States, of non-interference in the domestic affairs of States, of the prohibition of the threat or use of force and of universal respect for, and observance of, human rights and fundamental freedoms for all,

Bearing in mind the provisions of the Vienna Convention on the Law of Treaties of 1969,

Recognizing the relationship between the law of treaties between States and the law of treaties between States and international organizations or between international organizations,

Considering the importance of treaties between States and international organizations or between international organizations as a useful means of developing international relations and ensuring conditions for peaceful cooperation among nations, whatever their constitutional and social systems,

Having in mind the specific features of treaties to which international organizations are parties as subjects of international law distinct from States,

Noting that international organizations possess the capacity to conclude treaties, which is necessary for the exercise of their functions and the fulfilment of their purposes,

Recognizing that the practice of international organizations in concluding treaties with States or between themselves should be in accordance with their constituent instruments,

Affirming that nothing in the present Convention should be interpreted as affecting those relations between an international organization and its members which are regulated by the rules of the organization,

Affirming also that disputes concerning treaties, like other international disputes, should be settled, in conformity with the Charter of the United Nations, by peaceful means and in conformity with the principles of justice and international law,

Affirming also that the rules of customary international law will continue to govern questions not regulated by the provisions of the present Convention,

Have agreed as follows:

Part I Introduction

Article 1 Scope of the present Convention

The present Convention applies to:

(a) treaties between one or more States and one or more international organizations, and

(b) treaties between international organizations.

Article 2 Use of terms

1. For the purposes of the present Convention:

(a)     “treaty” means an international agreement governed by international law and concluded in written form:

(i)   between one or more States and one or more international organizations; or

(ii)  between international organizations,

whether that agreement is embodied in a single instrument or in two or more related instruments and whatever its particular designation;

(b)     “ratification” means the international act so named whereby a State establishes on the international plane its consent to be bound by a treaty;

(b bis) “act of formal confirmation” means an international act corresponding to that of ratification by a State, whereby an international organization establishes on the international plane its consent to be bound by a treaty;

(b ter) “acceptance”, “approval” and “accession” mean in each case the international act so named whereby a State or an international organization establishes on the international plane its consent to be bound by a treaty;

(c)     “full powers” means a document emanating from the competent authority of a State or from the competent organ of an international organization designating a person or persons to represent the State or the organization for negotiating, adopting or authenticating the text of a treaty, for expressing the consent of the State or of the organization to be bound by a treaty, or for accomplishing any other act with respect to a treaty;

(d)    “reservation” means a unilateral statement, however phrased or named, made by a State or by an international organization when signing, ratifying, formally confirming, accepting, approving or acceding to a treaty, whereby it purports to exclude or to modify the legal effect of certain provisions of the treaty in their application to that State or to that organization;

(e)    “negotiating State” and “negotiating organization” mean respectively:

(i)   a State, or

(ii)  an international organization,

which took part in the drawing up and adoption of the text of the treaty; f) “contracting State” and “contracting organization” mean respectively:

(i)   a State, or

(ii)  an international organization,

which has consented to be bound by the treaty, whether or not the treaty has entered into force;

(g)    “party” means a State or an international organization which has consented to be bound by the treaty and for which the treaty is in force;

(h)    “third State” and “third organization” mean respectively:

(i)   a State, or

(ii)        an international organization, not a party to the treaty;

(i)      “international organization” means an intergovernmental organization;

(j) “rules of the organization” means, in particular, the constituent instruments, decisions and resolutions adopted in accordance with them, and established practice of the organization.

2. The provisions of paragraph 1 regarding the use of terms in the present Convention are without prejudice to the use of those terms or to the meanings which may be given to them in the internal law of any State or in the rules of any internation
al organization.

Article 3

International agreements not within the scope of the present Convention

The fact that the present Convention does not apply:

(i)      to international agreements to which one or more States, one or more international organizations and one or more subjects of international law other than States or organizations are parties;

(ii)     to international agreements to which one or more international organizations and one or more subjects of international law other than States or organizations are parties;

(iii)    to international agreements not in written form between one or more States and one or more international organizations, or between international organizations; or

(iv)    to international agreements between subjects of international law other than States or international organizations;

shall not affect:

(a)    the legal force of such agreements;

(b)    the application to them of any of the rules set forth in the present Convention to which they would be subject under international law independently of the Convention;

(c)     the application of the Convention to the relations between States and international organizations or to the relations of organizations as between themselves, when those relations are governed by international agreements to which other subjects of international law are also parties.

Article 4

Non-retroactivity of the present Convention

Without prejudice to the application of any rules set forth in the present Convention to which treaties between one or more States and one or more international organizations or between international organizations would be subject under international law independently of the Convention, the Convention applies only to such treaties concluded after the entry into force of the present Convention with regard to those States and those organizations.

Article 5

Treaties constituting international organizations and treaties adopted within an international organization

The present Convention applies to any treaty between one or more States and one or more international organizations which is the constituent instrument of an international organization and to any treaty adopted within an international organization, without prejudice to any relevant rules of the organization.

Part II.

Conclusion and Entry into Force of Treaties section 1. conclusion of treaties

Article 6

Capacity of international organizations to conclude treaties

The capacity of an international organization to conclude treaties is governed by the rules of that organization.

Article 7 Full powers

1.   A person is considered as representing a State for the purpose of adopting or authenticating the text of a treaty or for the purpose of expressing the consent of the State to be bound by a treaty if:

(a)    that person produces appropriate full powers; or

(b)    it appears from practice or from other circumstances that it was the intention of the States and international organizations concerned to consider that person as representing the State for such purposes without having to produce full powers.

2.   In virtue of their functions and without having to produce full powers, the following are considered as representing their State:

(a)    Heads of State, Heads of Government and Ministers for Foreign Affairs, for the purpose of performing all acts relating to the conclusion of a treaty between one or more States and one or more international organizations;

(b)    representatives accredited by States to an international conference, for the purpose of adopting the text of a treaty between States and international organizations;

(c)     representatives accredited by States to an international organization or one of its organs, for the purpose of adopting the text of a treaty in that organization or organ;

(d) heads of permanent missions to an international organization, for the purpose of adopting the text of a treaty between the accrediting States and that organization.

3. A person is considered as representing an international organization for the purpose of adopting or authenticating the text of a treaty, or expressing the consent of that organization to be bound by a treaty, if:

(a) that person produces appropriate full powers; or

(b) it appears from the circumstances that it was the intention of the States and international organizations concerned to consider that person as representing the organization for such purposes, in accordance with the rules of the organization, without having to produce full powers.

Article 8

Subsequent confirmation of an act performed without authorization

An act relating to the conclusion of a treaty performed by a person who cannot be considered under article 7 as authorized to represent a State or an international organization for that purpose is without legal effect unless afterwards confirmed by that State or that organization.

Article 9 Adoption of the text

1.   The adoption of the text of a treaty takes place by the consent of all the States and international organizations or, as the case may be, all the organizations participating in its drawing up except as provided in paragraph 2.

2.   The adoption of the text of a treaty at an international conference takes place in accordance with the procedure agreed upon by the participants in that conference. If, however, no agreement is reached on any such procedure, the adoption of the text shall take place by the vote of two thirds of the participants present and voting unless by the same majority they shall decide to apply a different rule.

Article 10 Authentication of the text

1. The text of a treaty between one or more States and one or more international organizations is established as authentic and definitive:

(a)    by such procedure as may be provided for in the text or agreed upon by the States and organizations participating in its drawing up; or

(b)    failing such procedure, by the signature, signature ad referendum or initialling by the representatives of those States and those organizations of the text of the treaty or of the Final Act of a conference incorporating the text.

2. The text of a treaty between international organizations is established as authentic and definitive:

(a) by such procedure as may be provided for in the text or agreed upon by the organizations participating in its drawing up; or

(b) failing such procedure, by the signature, signature ad referendum or initialling by the representatives of those States and those organiz
ations of the text of the treaty or of the Final Act of a conference incorporating the text.

Article 11

Means of expressing consent to be bound by a treaty

1.   The consent of a State to be bound by a treaty may be expressed by signature, exchange of instruments constituting a treaty, ratification, acceptance, approval or accession, or by any other means if so agreed.

2.   The consent of an international organization to be bound by a treaty may be expressed by signature, exchange of instruments constituting a treaty, act of formal confirmation, acceptance, approval or accession, or by any other means if so agreed.

Article 12

Consent to be bound by a treaty expressed by signature

1.   The consent of a State or of an international organization to be bound by a treaty is expressed by the signature of the representative of that State or of that organization when:

(a)    the treaty provides that signature shall have that effect;

(b)    it is otherwise established that the negotiating States and negotiating organizations or, as the case may be, the negotiating organizations were agreed that signature should have that effect; or

(c)     the intention of the State or organization to give that effect to the signature appears from the full powers of its representative or was expressed during the negotiation.

2.   For the purposes of paragraph 1:

(a)    the initialling of a text constitutes a signature of the treaty when it is established that the negotiating States and negotiating organizations or, as the case may be, the negotiating organizations so agreed;

(b)    the signature ad referendum of a treaty by the representative of a State or an international organization, if confirmed by his State or organization, constitutes a full signature of the treaty.

Article 13

Consent to be bound by a treaty expressed by an exchange of instruments constituting a treaty

The consent of States or of international organizations to be bound by a treaty constituted by instruments exchanged between them is expressed by that exchange when:

(a)    the instruments provide that their exchange shall have that effect; or

(b)    it is otherwise established that those States and those organizations or, as the case may be, those organizations were agreed that the exchange of instruments should have that effect.

Article 14

Consent to be bound by a treaty expressed by ratification, act of formal confirmation, acceptance or approval

1.   The consent of a State to be bound by a treaty is expressed by ratification when:

(a)    the treaty provides for such consent to be expressed by means of ratification;

(b)    it is otherwise established that the negotiating States and negotiating organizations were agreed that ratification should be required;

(c)     the representative of the State has signed the treaty subject to ratification; or

(d)    the intention of the State to sign the treaty subject to ratification appears from the full powers of its representative or was expressed during the negotiation.

2.   The consent of an international organization to be bound by a treaty is expressed by an act of formal confirmation when:

(a)    the treaty provides for such consent to be expressed by means of an act of formal confirmation;

(b)    it is otherwise established that the negotiating States and negotiating organizations or, as the case may be, the negotiating organizations were agreed that an act of formal confirmation should be required;

(c)     the representative of the organization has signed the treaty subject to an act of formal confirmation; or

(d)    the intention of the organization to sign the treaty subject to an act of formal confirmation appears from the full powers of its representative or was expressed during the negotiation.

3.   The consent of a State or of an international organization to be bound by a treaty is expressed by acceptance or approval under conditions similar to those which apply to ratification or, as the case may be, to an act of formal confirmation.

Article 15

Consent to be bound by a treaty expressed by accession

The consent of a State or of an international organization to be bound by a treaty is expressed by accession when:

(a)    the treaty provides that such consent may be expressed by that State or that organization by means of accession;

(b)    it is otherwise established that the negotiating States and negotiating organizations or, as the case may be, the negotiating organizations were agreed that such consent may be expressed by that State or that organization by means of accession; or

(c)     all the parties have subsequently agreed that such consent may be expressed by that State or that organization by means of accession.

Article 16

Exchange or deposit of instruments of ratification, formal confirmation, acceptance, approval or accession

1.   Unless the treaty otherwise provides, instruments of ratification, instruments relating to an act of formal confirmation or instruments of acceptance, approval or accession establish the consent of a State or of an international organization to be bound by a treaty between one or more States and one or more international organizations upon:

(a)    their exchange between the contracting States and contracting organizations;

(b)    their deposit with the depositary; or

(c)     their notification to the contracting States and to the contracting organizations or to the depositary, if so agreed.

2.   Unless the treaty otherwise provides, instruments relating to an act of formal confirmation or instruments of acceptance, approval or accession establish the consent of an international organization to be bound by a treaty between international organizations upon:

(a)    their exchange between the contracting organizations;

(b)    their deposit with the depositary; or

(c)     their notification to the contracting organizations or to the depositary, if so agreed.

Article 17

Consent to be bound by part of a treaty and choice of differing provisions

1.   Without prejudice to articles 19 to 23, the consent of a State or of an international organization to be bound by part of a treaty is effective only if the treaty so permits, or if the contracting States and contracting organizations or, as the case may be, the contracting organizations so agree.

2.   The consent
of a State or of an international organization to be bound by a treaty which permits a choice between differing provisions is effective only if it is made clear to which of the provisions the consent relates.

Article 18

Obligation not to defeat the object and purpose of a treaty prior to its entry into force

A State or an international organization is obliged to refrain from acts which would defeat the object and purpose of a treaty when:

(a) that State or that organization has signed the treaty or has exchanged instruments constituting the treaty subject to ratification, act of formal confirmation, acceptance or approval, until that State or that organization shall have made its intention clear not to become a party to the treaty; or

(b) that State or that organization has expressed its consent to be bound by the treaty, pending the entry into force of the treaty and provided that such entry into force is not unduly delayed.

section 2. reservations

Article 19 Formulation of reservations

A State or an international organization may, when signing, ratifying, formally confirming, accepting, approving or acceding to a treaty, formulate a reservation unless:

(a) the reservation is prohibited by the treaty;

(b) the treaty provides that only specified reservations, which do not include the reservation in question, may be made; or

(c) in cases not falling under subparagraphs (a) and (b), the reservation is incompatible with the object and purpose of the treaty.

Article 20

Acceptance of and objection to reservations

1.A    reservation expressly authorized by a treaty does not require any subsequent acceptance by the contracting States and contracting organizations or, as the case may be, by the contracting organizations unless the treaty so provides.

2.   When it appears from the limited number of the negotiating States and negotiating organizations or, as the case may be, of the negotiating organizations and the object and purpose of a treaty that the application of the treaty in its entirety between all the parties is an essential condition of the consent of each one to be bound by the treaty, a reservation requires acceptance by all the parties.

3.   When a treaty is a constituent instrument of an international organization and unless it otherwise provides, a reservation requires the acceptance of the competent organ of that organization.

4.   In cases not falling under the preceding paragraphs and unless the treaty otherwise provides:

(a)    acceptance of a reservation by a contracting State or by a contracting organization constitutes the reserving State or international organization a party to the treaty in relation to the accepting State or organization if or when the treaty is in force for the reserving State or organization and for the accepting State or organization;

(b)    an objection by a contracting State or by a contracting organization to a reservation does not preclude the entry into force of the treaty as between the objecting State or international organization and the reserving State or organization unless a contrary intention is definitely expressed by the objecting State or organization;

(c)     an act expressing the consent of a State or of an international organization to be bound by the treaty and containing a reservation is effective as soon as at least one contracting State or one contracting organization has accepted the reservation.

5.   For the purposes of paragraphs 2 and 4, and unless the treaty otherwise provides, a reservation is considered to have been accepted by a State or an international organization if it shall have raised no objection to the reservation by the end of a period of twelve months after it was notified of the reservation or by the date on which it expressed its consent to be bound by the treaty, whichever is later.

Article 21

Legal effects of reservations and of objections to reservations 1.A reservation established with regard to another party in accordance with articles 19, 20 and 23:

(a)    modifies for the reserving State or international organization in its relations with that other party the provisions of the treaty to which the reservation relates to the extent of the reservation; and

(b)    modifies those provisions to the same extent for that other party in its relations with the reserving State or international organization.

2.   The reservation does not modify the provisions of the treaty for the other parties to the treaty inter se.

3.   When a State or an international organization objecting to a reservation has not opposed the entry into force of the treaty between itself and the reserving State or organization, the provisions to which the reservation relates do not apply as between the reserving State or organization and the objecting State or organization to the extent of the reservation.

Article 22

Withdrawal of reservations and of objections to reservations

1.   Unless the treaty otherwise provides, a reservation may be withdrawn at any time and the consent of a State or of an international organization which has accepted the reservation is not required for its withdrawal.

2.   Unless the treaty otherwise provides, an objection to a reservation may be withdrawn at any

time.

3.   Unless the treaty otherwise provides, or it is otherwise agreed:

(a)    the withdrawal of a reservation becomes operative in relation to a contracting State or a contracting organization only when notice of it has been received by that State or that organization;

(b)    the withdrawal of an objection to a reservation becomes operative only when notice of it has been received by the State or international organization which formulated the reservation.

Article 23 Procedure regarding reservations

1.   A reservation, an express acceptance of a reservation and an objection to a reservation must be formulated in writing and communicated to the contracting States and contracting organizations and other States and international organizations entitled to become parties to the treaty.

2.   If formulated when signing the treaty subject to ratification, act of formal confirmation, acceptance or approval, a reservation must be formally confirmed by the reserving State or international organization when expressing its consent to be bound by the treaty. In such a case the reservation shall be considered as having been made on the date of its confirmation.

3.   An express acceptance of, or an objection to, a reservation made previously to confirmation of the reservation does not itself require confirmation.

4. The withdrawal of a reservation or of an objection to a reservation must be formulated in writing.

section 3. entry into force and provisional applicati
on of treaties

Article 24 Entry into force

1.   A treaty enters into force in such manner and upon such date as it may provide or as the negotiating States and negotiating organizations or, as the case may be, the negotiating organizations may agree.

2.   Failing any such provision or agreement, a treaty enters into force as soon as consent to be bound by the treaty has been established for all the negotiating States and negotiating organizations or, as the case may be, all the negotiating organizations.

3.   When the consent of a State or of an international organization to be bound by a treaty is established on a date after the treaty has come into force, the treaty enters into force for that State or that organization on that date, unless the treaty otherwise provides.

4.   The provisions of a treaty regulating the authentication of its text, the establishment of consent to be bound by the treaty, the manner or date of its entry into force, reservations, the functions of the depositary and other matters arising necessarily before the entry into force of the treaty apply from the time of the adoption of its text.

Article 25 Provisional application

1.A   treaty or a part of a treaty is applied provisionally pending its entry into force if:

(a)    the treaty itself so provides; or

(b)    the negotiating States and negotiating organizations or, as the case may be, the negotiating organizations have in some other manner so agreed.

2.   Unless the treaty otherwise provides or the negotiating States and negotiating organizations or, as the case may be, the negotiating organizations have otherwise agreed, the provisional application of a treaty or a part of a treaty with respect to a State or an international organization shall be terminated if that State or that organization notifies the States and organizations with regard to which the treaty is being applied provisionally of its intention not to become a party to the treaty.

Part III. Observance, Application and Interpretation of Treaties section 1. observance of treaties

Article 26 Pacta sunt servanda

Every treaty in force is binding upon the parties to it and must be performed by them in good

faith.

Article 27

Internal law of States, rules of international organizations and observance of treaties

1. A State party to a treaty may not invoke the provisions of its internal law as justification for its failure to perform the treaty.

2.   An international organization party to a treaty may not invoke the rules of the organization as justification for its failure to perform the treaty.

3.   The rules contained in the preceding paragraphs are without prejudice to article 46.

section 2. application of treaties

Article 28 Non-retroactivity of treaties

Unless a different intention appears from the treaty or is otherwise established, its provisions do not bind a party in relation to any act or fact which took place or any situation which ceased to exist before the date of the entry into force of the treaty with respect to that party.

Article 29 Territorial scope of treaties

Unless a different intention appears from the treaty or is otherwise established, a treaty between one or more States and one or more international organizations is binding upon each State party in respect of its entire territory.

Article 30

Application of successive treaties relating to the same subject matter

1. The rights and obligations of States and international organizations parties to successive treaties relating to the same subject matter shall be determined in accordance with the following paragraphs.

2.   When a treaty specifies that it is subject to, or that it is not to be considered as incompatible with, an earlier or later treaty, the provisions of that other treaty prevail.

3.   When all the parties to the earlier treaty are parties also to the later treaty but the earlier treaty is not terminated or suspended in operation under article 59, the earlier treaty applies to the extent that its provisions are compatible with those of the later treaty.

4.   When the parties to the later treaty do not include all the parties to the earlier one:

(a)    as between two parties, each of which is a party to both treaties, the same rule applies as in paragraph 3;

(b)    as between a party to both treaties and a party to only one of the treaties, the treaty to which both are parties governs their mutual rights and obligations.

5.Paragraph       4 is without prejudice to article 41, or to any question of the termination or suspension of the operation of a treaty under article 60 or to any question of responsibility which may arise for a State or for an international organization from the conclusion or application of a treaty the provisions of which are incompatible with its obligations towards a State or an organization under another treaty.

6.   The preceding paragraphs are without prejudice to the fact that, in the event of a conflict between obligations under the Charter of the United Nations and obligations under a treaty, the obligations under the Charter shall prevail.

section 3. interpretation of treaties

Article 31 General rule of interpretation

1.   A treaty shall be interpreted in good faith in accordance with the ordinary meaning to be given to the terms of the treaty in their context and in the light of its object and purpose.

2.   The context for the purpose of the interpretation of a treaty shall comprise, in addition to the text, including its preamble and annexes:

(a)    any agreement relating to the treaty which was made between all the parties in connection with the conclusion of the treaty;

(b)    any instrument which was made by one or more parties in connection with the conclusion of the treaty and accepted by the other parties as an instrument related to the treaty.

3.   There shall be taken into account, together with the context:

(a) any subsequent agreement between the parties regarding the interpretation of the treaty or the application of its provisions;

(b)    any subsequent practice in the application of the treaty which establishes the agreement of the parties regarding its interpretation;

(c)     any relevant rules of international law applicable in the relations between the parties.

4. A special meaning shall be given to a term if it is established that the parties so intended.

Article 32 Supplementary means of interpretation

Recourse may be had to supplementary means of interpretation, including the preparatory work of
the treaty and the circumstances of its conclusion, in order to confirm the meaning resulting from the application of article 31, or to determine the meaning when the interpretation according to article 31:

(a)    leaves the meaning ambiguous or obscure; or

(b)    leads to a result which is manifestly absurd or unreasonable.

Article 33

Interpretation of treaties authenticated in two or more languages

1.   When a treaty has been authenticated in two or more languages, the text is equally authoritative in each language, unless the treaty provides or the parties agree that, in case of divergence, a particular text shall prevail.

2.   A version of the treaty in a language other than one of those in which the text was authenticated shall be considered an authentic text only if the treaty so provides or the parties so agree.

3.   The terms of a treaty are presumed to have the same meaning in each authentic text.

4.   Except where a particular text prevails in accordance with paragraph 1, when a comparison of the authentic texts discloses a difference of meaning which the application of articles 31 and 32 does not remove, the meaning which best reconciles the texts, having regard to the object and purpose of the treaty, shall be adopted.

section 4. treaties and third states or third organizations

Article 34

General rule regarding third States and third organizations

A treaty does not create either obligations or rights for a third State or a third organization without the consent of that State or that organization.

Article 35

Treaties providing for obligations for third States or third organizations

An obligation arises for a third State or a third organization from a provision of a treaty if the parties to the treaty intend the provision to be the means of establishing the obligation and the third State or the third organization expressly accepts that obligation in writing. Acceptance by the third organization of such an obligation shall be governed by the rules of that organization.

Article 36

Treaties providing for rights for third States or third organizations

1.   A right arises for a third State from a provision of a treaty if the parties to the treaty intend the provision to accord that right either to the third State, or to a group of States to which it belongs, or to all States, and the third State assents thereto. Its assent shall be presumed so long as the contrary is not indicated, unless the treaty otherwise provides.

2.   A right arises for a third organization from a provision of a treaty if the parties to the treaty intend the provision to accord that right either to the third organization, or to a group of international organizations to which it belongs, or to all organizations, and the third organization assents thereto. Its assent shall be governed by the rules of the organization.

3.   A State or an international organization exercising a right in accordance with paragraph 1 or 2 shall comply with the conditions for its exercise provided for in the treaty or established in conformity with the treaty.

Article 37

Revocation or modification of obligations or rights of third States or third organizations

1.   When an obligation has arisen for a third State or a third organization in conformity with article 35, the obligation may be revoked or modified only with the consent of the parties to the treaty and of the third State or the third organization, unless it is established that they had otherwise agreed.

2.   When a right has arisen for a third State or a third organization in conformity with article 36, the right may not be revoked or modified by the parties if it is established that the right was intended not to be revocable or subject to modification without the consent of the third State or the third organization.

3. The consent of an international organization party to the treaty or of a third organization, as provided for in the foregoing paragraphs, shall be governed by the rules of that organization.

Article 38

Rules in a treaty becoming binding on third States or third organizations through international custom

Nothing in articles 34 to 37 precludes a rule set forth in a treaty from becoming binding upon a third State or a third organization as a customary rule of international law, recognized as such.

Part IV.

Amendment and Modification of Treaties

Article 39

General rule regarding the amendment of treaties

1.A    treaty may be amended by agreement between the parties. The rules laid down in Part II apply to such an agreement except insofar as the treaty may otherwise provide.

2.   The consent of an international organization to an agreement provided for in paragraph 1 shall be governed by the rules of that organization.

Article 40 Amendment of multilateral treaties

1.   Unless the treaty otherwise provides, the amendment of multilateral treaties shall be governed by the following paragraphs.

2.   Any proposal to amend a multilateral treaty as between all the parties must be notified to all the contracting States and all the contracting organizations, each one of which shall have the right to take part in:

(a)    the decision as to the action to be taken in regard to such proposal;

(b)    the negotiation and conclusion of any agreement for the amendment of the treaty.

3.   Every State or international organization entitled to become a party to the treaty shall also be entitled to become a party to the treaty as amended.

4.   The amending agreement does not bind any State or international organization already a party to the treaty which does not become a party to the amending agreement; article 30, paragraph 4 (b), applies in relation to such State or organization.

5.   Any State or international organization which becomes a party to the treaty after the entry into force of the amending agreement shall, failing an expression of a different intention by that State or that organization:

(a) be considered as a party to the treaty as amended; and

(b) be considered as a party to the unamended treaty in relation to any party to the treaty not bound by the amending agreement.

Article 41

Agreements to modify multilateral treaties between certain of the parties only

1. Two or more of the parties to a multilateral treaty may conclude an agreement to modify the treaty as between themselves alone if:

(a)    the possibility of such a modification is provided for by the treaty; or

(b)    the modifi
cation in question is not prohibited by the treaty and:

(i)   does not affect the enjoyment by the other parties of their rights under the treaty or the performance of their obligations;

(ii)  does not relate to a provision, derogation from which is incompatible with the effective execution of the object and purpose of the treaty as a whole.

2. Unless in a case falling under paragraph 1 (a) the treaty otherwise provides, the parties in question shall notify the other parties of their intention to conclude the agreement and of the modification to the treaty for which it provides.

Part V.

Invalidity, Termination and Suspension of the Operation of Treaties

section 1. general provisions

Article 42

Validity and continuance in force of treaties

1.   The validity of a treaty or of the consent of a State or an international organization to be bound by a treaty may be impeached only through the application of the present Convention.

2.   The termination of a treaty, its denunciation or the withdrawal of a party, may take place only as a result of the application of the provisions of the treaty or of the present Convention. The same rule applies to suspension of the operation of a treaty.

Article 43

Obligations imposed by international law independently of a treaty

The invalidity, termination or denunciation of a treaty, the withdrawal of a party from it, or the suspension of its operation, as a result of the application of the present Convention or of the provisions of the treaty, shall not in any way impair the duty of any State or of any international organization to

fulfil any obligation embodied in the treaty to which that State or that organization would be subject under international law independently of the treaty.

Article 44 Separability of treaty provisions

1.A    right of a party, provided for in a treaty or arising under article 56, to denounce, withdraw from or suspend the operation of the treaty may be exercised only with respect to the whole treaty unless the treaty otherwise provides or the parties otherwise agree.

2.   A ground for invalidating, terminating, withdrawing from or suspending the operation of a treaty recognized in the present Convention may be invoked only with respect to the whole treaty except as provided in the following paragraphs or in article 60.

3.   If the ground relates solely to particular clauses, it may be invoked only with respect to those clauses where:

(a)     the said clauses are separable from the remainder of the treaty with regard to their application;

(b)     it appears from the treaty or is otherwise established that acceptance of those clauses was not an essential basis of the consent of the other party or parties to be bound by the treaty as a whole; and

(c)     continued performance of the remainder of the treaty would not be unjust.

4.   In cases falling under articles 49 and 50, the State or international organization entitled to invoke the fraud or corruption may do so with respect either to the whole treaty or, subject to paragraph 3, to the particular clauses alone.

5.   In cases falling under articles 51, 52 and 53, no separation of the provisions of the treaty is permitted.

Article 45

Loss of a right to invoke a ground for invalidating, terminating, withdrawing from or suspending the operation of a treaty

1.A State may no longer invoke a ground for invalidating, terminating, withdrawing from or suspending the operation of a treaty under articles 46 to 50 or articles 60 and 62 if, after becoming aware of the facts:

(a)     it shall have expressly agreed that the treaty is valid or remains in force or continues in operation, as the case may be; or

(b)     it must by reason of its conduct be considered as having acquiesced in the validity of the treaty or in its maintenance in force or in operation, as the case may be.

2. An international organization may no longer invoke a ground for invalidating, terminating, withdrawing from or suspending the operation of a treaty under articles 46 to 50 or articles 60 and 62 if, after becoming aware of the facts:

(a)     it shall have expressly agreed that the treaty is valid or remains in force or continues in operation, as the case may be; or

(b)     it must by reason of the conduct of the competent organ be considered as having renounced the right to invoke that ground.

section 2. invalidity of treaties

Article 46

Provisions of internal law of a State and rules of an international organization regarding competence to conclude treaties

1.A    State may not invoke the fact that its consent to be bound by a treaty has been expressed in violation of a provision of its internal law regarding competence to conclude treaties as invalidating its consent unless that violation was manifest and concerned a rule of its internal law of fundamental importance.

2.   An international organization may not invoke the fact that its consent to be bound by a treaty has been expressed in violation of the rules of the organization regarding competence to conclude treaties as invalidating its consent unless that violation was manifest and concerned a rule of fundamental importance.

3.   A violation is manifest if it would be objectively evident to any State or any international organization conducting itself in the matter in accordance with the normal practice of States and, where appropriate, of international organizations and in good faith.

Article 47

Specific restrictions on authority to express the consent of a State or an international organization

If the authority of a representative to express the consent of a State or of an international organization to be bound by a particular treaty has been made subject to a specific restriction, his omission to observe that restriction may not be invoked as invalidating the consent expressed by him unless the restriction was notified to the negotiating States and negotiating organizations prior to his expressing such consent.

Article 48 Error

1. A State or an international organization may invoke an error in a treaty as invalidating its consent to be bound by the treaty if the error relates to a fact or situation which was assumed by that

State or that organization to exist at the time when the treaty was concluded and formed an essential basis of the consent of that State or that organization to be bound by the treaty.

2. Paragraph 1 shall not apply if the State or international organization in question contributed by its own conduct to the error or if the circumstances were such as to put that State or that organization on notice of a possible error.

3. An error relating only to the wording of the text of a treaty does not affect its validity; article 80 then applies.

Article 49 Fraud

A State or an international organization induced to conclude a treaty by the fraudulent conduct of a negotiating State or a negotiating organization may invoke the fraud as invalidating its consent to be bound by the treaty.

Article 50

Corruption of a representative of a State or of an international organization

A State or an international organization the expression of whose consent to be bound by a treaty has been procured through the corruption of its representative directly or indirectly by a negotiating State or a negotiating organization may invoke such corruption as invalidating its consent to be bound by the treaty.

Article 51

Coercion of a representative of a State or of an international organization

The expression by a State or an international organization of consent to be bound by a treaty which has been procured by the coercion of the representative of that State or that organization through acts or threats directed against him shall be without any legal effect.

Article 52

Coercion of a State or of an international organization by the threat or use of force

A treaty is void if its conclusion has been procured by the threat or use of force in violation of the principles of international law embodied in the Chatter of the United Nations.

Article 53

Treaties conflicting with a peremptory norm of general international law (jus cogens)

A treaty is void if, at the time of its conclusion, it conflicts with a peremptory norm of general international law. For the purposes of the present Convention, a peremptory norm of general

international law is a norm accepted and recognized by the international community of States as a whole as a norm from which no derogation is permitted and which can be modified only by a subsequent norm of general international law having the same character.

section 3. termination and suspension of the operation of treaties

Article 54

Termination of or withdrawal from a treaty under its provisions or by consent of the parties

The termination of a treaty or the withdrawal of a party may take place:

(a)    in conformity with the provisions of the treaty; or

(b)    at any time by consent of all the parties after consultation with the contracting States and contracting organizations.

Article 55

Reduction of the parties to a multilateral treaty below the number necessary for its entry into force

Unless the treaty otherwise provides, a multilateral treaty does not terminate by reason only of the fact that the number of the parties falls below the number necessary for its entry into force.

Article 56

Denunciation of or withdrawal from a treaty containing no provision regarding termination, denunciation or withdrawal

1.   A treaty which contains no provision regarding its termination and which does not provide for denunciation or withdrawal is not subject to denunciation or withdrawal unless:

(a)    it is established that the parties intended to admit the possibility of denunciation or withdrawal; or

(b)    a right of denunciation or withdrawal may be implied by the nature of the treaty.

2.   A party shall give not less than twelve months’ notice of its intention to denounce or withdraw from a treaty under paragraph 1.

Article 57

Suspension of the operation of a treaty under its provisions or by consent of the parties

The operation of a treaty in regard to all the parties or to a particular party may be suspended:

(a) in conformity with the provisions of the treaty; or

(b) at any time by consent of all the parties after consultation with the contracting States and contracting organizations.

Article 58

Suspension of the operation of a multilateral treaty by agreement between certain of the parties only

1.   Two or more parties to a multilateral treaty may conclude an agreement to suspend the operation of provisions of the treaty, temporarily and as between themselves alone, if:

(a)    the possibility of such a suspension is provided for by the treaty; or

(b)    the suspension in question is not prohibited by the treaty and:

(i)   does not affect the enjoyment by the other parties of their rights under the treaty or the performance of their obligations;

(ii)        is not incompatible with the object and purpose of the treaty.

2.   Unless in a case falling under paragraph 1 (a) the treaty otherwise provides, the parties in question shall notify the other parties of their intention to conclude the agreement and of those provisions of the treaty the operation of which they intend to suspend.

Article 59

Termination or suspension of the operation of a treaty implied by conclusion of a later treaty

1.A   treaty shall be considered as terminated if all the parties to it conclude a later treaty relating to the same subject matter and:

(a)    it appears from the later treaty or is otherwise established that the parties intended that the matter should be governed by that treaty; or

(b)    the provisions of the later treaty are so far incompatible with those of the earlier one that the two treaties are not capable of being applied at the same time.

2.   The earlier treaty shall be considered as only suspended in operation if it appears from the later treaty or is otherwise established that such was the intention of the parties.

Article 60

Termination or suspension of the operation of a treaty as a consequence of its breach

1.A material breach of a bilateral treaty by one of the parties entitles the other to invoke the breach as a ground for terminating the treaty or suspending its operation in whole or in part.

2. A material breach of a multilateral treaty by one of the parties entitles:

(a)    the other parties by unanimous agreement to suspend the operation of the treaty in whole or in part or to terminate it either:

(i)   in the relations between themselves and the defaulting State or international organization; or

(ii)        as between all the parties;

(b)    a party specially affected by the breach to invoke it as a ground for suspending the operati
on of the treaty in whole or in part in the relations between itself and the defaulting State or international organization;

(c)     any party other than the defaulting State or international organization to invoke the breach as a ground for suspending the operation of the treaty in whole or in part with respect to itself if the treaty is of such a character that a material breach of its provisions by one party radically changes the position of every party with respect to the further performance of its obligations under the treaty.

3.   A material breach of a treaty, for the purposes of this article, consists in:

(a)    a repudiation of the treaty not sanctioned by the present Convention; or

(b)    the violation of a provision essential to the accomplishment of the object or purpose of the treaty.

4.   The foregoing paragraphs are without prejudice to any provision in the treaty applicable in the event of a breach.

5.   Paragraphs 1 to 3 do not apply to provisions relating to the protection of the human person contained in treaties of a humanitarian character, in particular to provisions prohibiting any form of reprisals against persons protected by such treaties.

Article 61

Supervening impossibility of performance

1.A    party may invoke the impossibility of performing a treaty as a ground for terminating or withdrawing from it if the impossibility results from the permanent disappearance or destruction of an object indispensable for the execution of the treaty. If the impossibility is temporary, it may be invoked only as a ground for suspending the operation of the treaty.

2.   Impossibility of performance may not be invoked by a party as a ground for terminating, withdrawing from or suspending the operation of a treaty if the impossibility is the result of a breach by that party either of an obligation under the treaty or of any other international obligation owed to any other party to the treaty.

Article 62 Fundamental change of circumstances

1.   A fundamental change of circumstances which has occurred with regard to those existing at the time of the conclusion of a treaty, and which was not foreseen by the parties, may not be invoked as a ground for terminating or withdrawing from the treaty unless:

(a)     the existence of those circumstances constituted an essential basis of the consent of the parties to be bound by the treaty; and

(b)     the effect of the change is radically to transform the extent of obligations still to be performed under the treaty.

2.   A fundamental change of circumstances may not be invoked as a ground for terminating or withdrawing from a treaty between two or more States and one or more international organizations if the treaty establishes a boundary.

3.   A fundamental change of circumstances may not be invoked as a ground for terminating or withdrawing from a treaty if the fundamental change is the result of a breach by the party invoking it either of an obligation under the treaty or of any other international obligation owed to any other party to the treaty.

4.   If, under the foregoing paragraphs, a party may invoke a fundamental change of circumstances as a ground for terminating or withdrawing from a treaty it may also invoke the change as a ground for suspending the operation of the treaty.

Article 63

Severance of diplomatic or consular relations

The severance of diplomatic or consular relations between States Parties to a treaty between two or more States and one or more international organizations does not affect the legal relations established between those States by the treaty except insofar as the existence of diplomatic or consular relations is indispensable for the application of the treaty.

Article 64

Emergence of a new peremptory norm of general international law (jus cogens)

If a new peremptory norm of general international law emerges, any existing treaty which is in conflict with that norm becomes void and terminates.

section 4. procedure

Article 65

Procedure to be followed with respect to invalidity, termination, withdrawal from or suspension of the operation of a treaty

1.A    party which, under the provisions of the present Convention, invokes either a defect in its consent to be bound by a treaty or a ground for impeaching the validity of a treaty, terminating it, withdrawing from it or suspending its operation, must notify the other parties of its claim. The notification shall indicate the measure proposed to be taken with respect to the treaty and the reasons therefor.

2.   If, after the expiry of a period which, except in cases of special urgency, shall not be less than three months after the receipt of the notification, no party has raised any objection, the party making the notification may carry out in the manner provided in article 67 the measure which it has proposed.

3.   If, however, objection has been raised by any other party, the parties shall seek a solution through the means indicated in Article 33 of the Charter of the United Nations.

4.   The notification or objection made by an international organization shall be governed by the rules of that organization.

5.   Nothing in the foregoing paragraphs shall affect the rights or obligations of the parties under any provisions in force binding the parties with regard to the settlement of disputes.

6.   Without prejudice to article 45, the fact that a State or an international organization has not previously made the notification prescribed in paragraph 1 shall not prevent it from making such notification in answer to another party claiming performance of the treaty or alleging its violation.

Article 66

Procedures for judicial settlement, arbitration and conciliation

1.   If, under paragraph 3 of article 65, no solution has been reached within a period of twelve months following the date on which the objection was raised, the procedures specified in the following paragraphs shall be followed.

2.   With respect to a dispute concerning the application or the interpretation of article 53 or 64:

(a)     if a State is a party to the dispute with one or more States, it may, by a written application, submit the dispute to the International Court of Justice for a decision;

(b)     if a State is a party to the dispute to which one or more international organizations are parties, the State may, through a Member State of the United Nations if necessary, request the General Assembly or the Security Council or, where appropriate, the competent organ of an international organization which is a party to the dispute and is authorized in accordance with Article 96 of the Charter of the United Nations, to request an advisory opinion of the International Court of Justice in accordance with Article 65 of the Statute of the Court;

(c)