Vienna Convention on Diplomatic Relations in the United States

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.

SECTION 4. TREATIES AND THIRD STATES

Article 34
General rule regarding third States

A treaty does not create either obligations or rights for a third State
without its consent.

Article 35
Treaties providing for obligations for third States

An obligation arises for a third State 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 expressly accepts that obligation in
writing.

Article 36
Treaties providing for rights for third States

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 State exercising a right in accordance with paragraph 1 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

1. When an obligation has arisen for a third State 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, unless it is
established that they had otherwise agreed.

2. When a right has arisen for a third State 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.

Article 38
Rules in a treaty becoming binding on third States
through international custom

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

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.