Article 3 International agreements not within the scope of the present Convention

The fact that the present Convention does not apply to international agreements concluded between States and other subjects of international law or between such other subjects of international law, or to international agreements not in written form, 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 of States as between themselves under 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 would be subject under international law independently of the Convention, the Convention applies only to treaties which are concluded by States after the entry into force of the present Convention with regard to such States.

Article 5 Treaties constituting international organizations and treaties adopted within an international organization
The present Convention applies to any treaty 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 States to conclude treaties
Every State possesses capacity to conclude treaties.

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)he produces appropriate full powers; or
(b)it appears from the practice of the States concerned or from other circumstances that their intention was to consider that person as representing the State for such purposes and to dispense with 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;
(b)heads of diplomatic missions, for the purpose of adopting the text of a treaty between the accrediting State and the State to which they are accredited;
(c) representatives accredited by States to an international conference or to an international organization or one of its organs, for the purpose of adopting the text of a treaty in that conference, organization or organ.

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 for that purpose is without legal effect unless afterwards confirmed by that State.

Article 9 Adoption of the text

1. The adoption of the text of a treaty takes place by the consent of all the States 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 by the vote of two-thirds of the States present and voting, unless by the same majority they shall decide to apply a different rule.

Article 10 Authentication of the text
The text of a treaty is established as authentic and definitive: (a)
by such procedure as may be provided for in the text or agreed upon by the States participating in its drawing up; or
(b)failing such procedure, by the signature, signature ad referendum or initialling by the representatives of those States 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
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.

Article 12 Consent to be bound by a treaty expressed by signature
1. The consent of a State to be bound by a treaty is expressed by the signature of its representative when:
(a) the treaty provides that signature shall have that effect;
(b) it is otherwise established that the negotiating States were agreed that signature should have that effect; or
(c) the intention of the State 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 so agreed;
(b) the signature ad referendum of a treaty by a representative, if confirmed by his State, 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 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 were agreed that the exchange of instruments should have that effect.

Article 14 Consent to be bound by a treaty expressed by ratification, 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 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 a State to be bound by a treaty is expressed by acceptance or approval under conditions similar to those which apply to ratification.

Article 15 Consent to be bound by a treaty expressed by accession

The consent of a State to be bound by a treaty is expressed by accession when:
(a) the treaty provides that such consent may be expressed by that State by means of accession;
(b) it is otherwise established that the negotiating States were agreed that such consent may be expressed by that State by means of accession; or
(c) all the parties have subsequently agreed that such consent may be expressed by that State by means of accession.

Article 16 Exchange or deposit of instruments of ratification, acceptance, approval or accession
Unless the treaty otherwise provides, instruments of ratification, acceptance, approval or accession establish the consent of a State to be bound by a treaty upon:
(a) their exchange between the contracting States;
(b) their deposit with the depositary; or
(c) their notification to the contracting States or to the depositary, if 50 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 to be bound by part of a treaty is effective only if the treaty so permits or the other contracting States so agree.
2. The consent of a State 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 is obliged to refrain from acts which would defeat the object and purpose of a treaty when:
(a) it has signed the treaty or has exchanged instruments constituting the treaty subject to ratification, acceptance or approval, until it shall have made its intention clear not to become a party to the treaty; or
(b) it 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 may, when signing, ratifying, 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 sub-paragraphs (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 other contracting States unless the treaty so provides.
2. When it appears from the limited number of the negotiating States 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 by another contracting State of a reservation constitutes the reserving State a party to the treaty in relation to that other State if or when the treaty is in force for those States;
(b) an objection by another contracting State to a reservation does not preclude the entry into force of the treaty as between the objecting and reserving States unless a contrary intention is definitely expressed by the objecting State;
(c) an act expressing a State's consent to be bound by the treaty and containing a reservation is effective as soon as at least one other contracting State 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 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 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.
2. The reservation does not modify the provisions of the treaty for the other parties to the treaty inter se.
3. When a State objecting to a reservation has not opposed the entry into force of the treaty between itself and the reserving State, the provisions to which the reservation relates do not apply as between the two States 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 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 another contracting State only when notice of it has been received by that State;
(b) the withdrawal of an objection to a reservation becomes operative only when notice of it has been received by the State 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 other States entitled to become parties to the treaty.
2. If formulated when signing the treaty subject to ratification, acceptance or approval, a reservation must be formally confirmed by the reserving State 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 application 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 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.
3. When the consent of a State 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 on that date, unless the treaty otherwise provides.
4. The provisions of a treaty regulating the authentication of its text, the establishment of the consent of States 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 have in some other manner so agreed.
2. Unless the treaty otherwise provides or the negotiating States have otherwise agreed, the provisional application of a treaty or a part of a treaty with respect to a State shall be terminated if that State notifies the other States between 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 and observance of treaties
A party may not invoke the provisions of its internal law as justification for its failure to perform a treaty. This rule is 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 is binding upon each party in respect of its entire territory.

Article 30 Application of successive treaties relating to the same subject-matter
1. Subject to Article 103 of the Charter of the United Nations, the rights and obligations of States 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 only to the extent that its provisions are compatible with those of the latter treaty.
4. When the parties to the later treaty do not include all the parties to the earlier one:
(a) as between States parties to both treaties the same rule applies as in paragraph 3;
(b) as between a State party to both treaties and a State party to only one of the treaties, the treaty to which both States 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 from the conclusion or application of a treaty, the provisions of which are incompatible with its obligations towards another State under another treaty.


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 connexion with the conclusion of the treaty;
(b) any instrument which was made by one or more parties in connexion 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 the 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.