1. Introduction
A treaty is one of the most important and binding sources of international law. It is a formal written agreement between two or more sovereign states or international organizations, governed by international law.
2. Definition of Treaty
According to Vienna Convention on the Law of Treaties (1969), Article 2(1)(a):
“A treaty is an international agreement concluded between states in written form and governed by international law...”
3. Legal Status
Treaties are legally binding like contracts under domestic law. Once signed and ratified, parties are under obligation to perform them in good faith (Pacta Sunt Servanda).
4. Parties to a Treaty
- Sovereign states
- International organizations (e.g., UN, WHO)
- Multiple states/entities can be party to a single treaty (multilateral)
1.2.5 5. Formation of a Treaty
Treaty-making generally involves the following steps:
1.2.5.1 a) Negotiation
States come together and discuss the terms and objectives.
1.2.5.2 b) Adoption
The final draft is adopted through consent of states.
1.2.5.3 c) Authentication
The text is authenticated through signature or other agreed method.
1.2.5.4 d) Ratification
Each state gives final approval via domestic legal procedures.
1.2.5.5 e) Registration
Treaties must be registered with the UN (Article 102 of UN Charter).
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1.2.6 6. Classification of Treaties
1.2.6.1 a) Bilateral Treaties
Between two states only (e.g., Peace Treaty between Egypt and Israel, 1979)
1.2.6.2 b) Multilateral Treaties
Among several states (e.g., UN Charter, Geneva Conventions)
1.2.6.3 c) Law-making Treaties
Create new rules of international law
1.2.6.4 d) Contractual Treaties
Create rights and obligations only for the parties involved
1.2.7 7. Binding Nature – Pacta Sunt Servanda
This principle means “agreements must be kept”.
Once a treaty is validly entered, it binds the parties to its terms unless lawfully terminated or
suspended.
1.2.8 8. Interpretation of Treaties
Vienna Convention guides treaty interpretation based on:
Ordinary meaning of words
Context and object
Subsequent practice of states
1.2.9 9. Invalidity and Termination of Treaties
A treaty may be considered invalid due to:
Coercion
Fraud or corruption
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Conflict with jus cogens (peremptory norms)
Termination may occur:
By consent
Material breach
Change of circumstances (Rebus Sic Stantibus)
1.2.10 10. Reservations in Treaties
A reservation is a unilateral statement made by a state to exclude or modify the legal effect of
certain provisions.
Permitted unless:
Prohibited by treaty
Incompatible with object and purpose
1.2.11 11. Role of Treaties in International Relations
Treaties are used to:
Maintain peace and security
Regulate trade and environment
Establish international organizations
They enhance cooperation and predictability in global affairs.
1.2.12 12. Conclusion
Treaties serve as the backbone of international legal relations, creating enforceable obligations
between states. The Vienna Convention on the Law of Treaties provides a universal
framework to regulate their formation, operation, and termination.
