Vienna Convention on the Law of Treaties

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.

Author: international