Vienna Convention on the Law of Treaties
Article 24: Entry into Force
A treaty enters into force as specified in its provisions or as agreed upon by the negotiating states. If no such provision or agreement exists, a treaty enters into force upon consent of all negotiating states to be bound by it.
Article 25: Provisional Application
A treaty or part thereof is applied provisionally pending its entry into force if: a) the treaty itself so provides, or b) the negotiating states have agreed otherwise.
Observance, Application, and Interpretation of Treaties
Article 26: Pacta Sunt Servanda
Every treaty in force is binding upon the parties and must be performed in good faith.
Article 27: Internal Law and Observance of Treaties
A party may not invoke internal law to justify breach of a treaty. This rule is without prejudice to Article 46.
Effects of Treaties
Article 28: Non-Retroactivity
Treaty obligations apply to the future. Parties may agree to retroactive effects.
Effects in Space
A treaty is binding on the territory where a state exercises sovereignty.
Article 30: Application of Successive Treaties
- When a treaty specifies its relationship to an earlier or later treaty, those specifications prevail.
- When all parties to an earlier treaty are also parties to a later treaty, but the earlier treaty is not terminated or suspended, the earlier treaty applies only to the extent its provisions are compatible with the later treaty.
- When the parties to a later treaty do not include all parties to an earlier treaty, specific rules apply (not detailed here).
Article 31: General Rule of Interpretation
A treaty shall be interpreted in good faith according to the ordinary meaning of its terms in their context, taking into account its object and purpose. Interpretation includes the text, preamble, and annexes.
Invalidity, Termination, and Suspension of Treaties
Invalidity
Invalidity is a legal sanction imposed on a treaty flawed at its conclusion.
Termination
Termination is the cessation of a treaty’s legal effects for the future.
Article 42: Grounds for Invalidity
Grounds for invalidity are those specified in the convention or set by the parties.
Article 43: Obligations Independent of a Treaty
If a treaty is declared void, obligations under international law independent of the treaty remain in force.
Grounds for Invalidation
Article 46: Internal Law as Grounds for Invalidity
Internal law cannot be invoked to invalidate a treaty unless the violation is manifest and objectively evident to any state acting in good faith.
Article 47: Restrictions on Authority
Specific restrictions on a representative’s authority to express consent can invalidate a treaty.
Causes of Defects in Consent
Article 48: Error
A state may invoke error if it relates to a fact or situation assumed when the treaty was concluded and formed an essential basis of consent. This does not apply if the state contributed to the error or was advised of its possibility. Errors in wording are addressed in Article 79.
Article 49: Fraud
Fraudulent conduct by another state can invalidate consent.
Article 50: Corruption
Corruption of a state’s representative can invalidate consent.
Article 51: Coercion of a Representative
Coercion of a state’s representative through acts or threats renders consent invalid.
Article 52: Coercion of a State
A treaty is void if procured by threat or use of force violating international law.
Article 53: Conflict with Peremptory Norm
A treaty conflicting with a peremptory norm of general international law (jus cogens) is void.
Termination of a Treaty
Article 54: Termination or Withdrawal
Termination or withdrawal can occur under the treaty’s provisions or by consent of all parties after consultation.
Article 62: Fundamental Change of Circumstances (Rebus Sic Stantibus)
A fundamental change of circumstances not foreseen by the parties can be invoked for termination or withdrawal only if the circumstances were an essential basis of consent and the change radically alters obligations.