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Every treaty in force is binding upon the parties to it and must be performed by them in good faith.
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.
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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.
Recourse may be had to supplementary means of interpretation, including the preparatory work of the treaty and the cirqumstances of ist 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.
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A treaty does not create either obligations or rights for a third state without ist consent.
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1.The validity of a treaty or of the consent of a State 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.
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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. A violation is manifest if it would be objectively evident to any State conducting itself in the matter in accordance with normal practice and in good faith.
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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
(ii)
as between all the parties;
(b)
a party specially affected by the breach to invoke it as a ground for suspending the operation of the treaty in whole or in part in the relations between itself and the defaulting State;
(c)
any party other than the defaulting State 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.
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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:
(a)
if the treaty establishes a boundary; or
(b)
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.
3. 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.