Pacta Sunt Servanda

Pacta sunt servanda means that agreements must be kept. In treaty law, it requires every treaty in force to be treated as binding by its parties and performed in good faith, rather than regarded as a merely political promise.

Legal formulation

The principle is codified in Article 26 of the Vienna Convention on the Law of Treaties, 1969. It is also recognised as a foundational rule of customary international law.

• The obligation applies to treaties that are valid and in force for the state concerned.
• Each party must fulfil the obligations it accepted according to the treaty's terms.
• Good-faith performance excludes deliberate evasion or conduct designed to frustrate the agreed obligations.

Domestic law and treaty performance

Under Article 27 of the Vienna Convention, a state generally cannot invoke its internal law as justification for failing to perform a treaty. It must therefore arrange its domestic legal and administrative conduct as necessary to meet its international obligations.

• A change of government, policy preference or perceived inconvenience does not by itself excuse non-performance.
• Failure to secure required domestic implementation may leave the state internationally responsible, even where the treaty is not directly enforceable in domestic courts.

Scope and lawful qualifications

The principle does not make every treaty permanent or unalterable. Amendment, withdrawal, suspension or termination remains possible when permitted by the treaty or by the recognised rules of treaty law.

• A state cannot unilaterally disregard obligations merely by declaring that its national interest has changed.
• Treaty performance remains subject to superior rules of international law, including peremptory norms.

Indian constitutional setting

Article 51(c) directs the State to foster respect for international law and treaty obligations. Article 253 empowers Parliament to legislate for implementing treaties, agreements and conventions.