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Law Notes International Law Notes

Treaties Problem Question Notes

Updated Treaties Problem Question Notes Notes

International Law Notes

International Law

Approximately 258 pages

International Law notes fully updated for recent exams at Oxford and Cambridge. These notes cover all the major LLB aspects and so are perfect for anyone doing an LLB in the UK or a great supplement for those doing LLBs abroad, whether that be in Ireland, Canada, Hong Kong or Malaysia (University of London). These notes were formed directly from a reading of the cases and main texts and are vigorous, concise and very well written. Everything is conveniently split up by topic as you can see by ...

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Treaties PQ Notes


Art 2(1)(a): “‘Treaty’ means an international agreement concluded between States in written form and governed by international law, whether embodied in a single instrument or in two or more related instruments and whatever its particular designation”.

Additional requirements

Intention to create legal relations

ILC: This is implicit in the phrase “governed by international law” in Art 2(1)(a), VCLT. requirement explains why Memoranda of Understanding and other written soft law instruments are not treaties

Greece v Turkey (Aegean Sea Continental Shelf): A “joint communique” issued by the Greek and Turkish PMs was not a treaty because an intention to create legal relations could not be found.


Iran v USA (Oil Platforms): Although a treaty is legally binding, a particular provision in it may be “drafted in terms so general that by itself it is not capable of generating legal rights and obligations”. Thus, Art 1 of the Treaty of Friendship 1955, which provided that “there shall be firm and ensuring peace and sincere friendship between the United States and… Iran”, did not generate legal rights and obligations (although it could be used to interpret the rest of the treaty).

No need for registration

Art 80, VCLT; Art 102(1), UN Charter: Treaties should be registered, but registration does not make a treaty valid nor does non-registration make a treaty non-valid.

Qatar v Bahrain: “Non-registration or late registration… does not have any consequences for the validity of the actual validity of the treaty, which remains no less binding upon the parties.”

Substantive, not formal, determination

Qatar v Bahrain: “[I]nternational agreements may take a number of forms and be given a diversity of names”.

Greece v Turkey (Aegean Sea Continental Shelf): Whether an agreement constitutes a treaty
“essentially depends on the nature of the act or transaction to which [it] gives expression; and it does not settle the question simply to refer to the form… in which that act or transaction is embodied”. Rather, the court “must have regard to all of its actual terms and the particular circumstances in which it was drawn up”.

Qatar v Bahrain: An exchange of letters can constitute a binding treaty. Meeting minutes which are “not a simple record” of the meeting, but “enumerate the commitments to which the Parties have consented”, can “create rights and obligations in international law for the Parties” and thus constitute a treaty. In these circumstances, a purported intention not to conclude a treaty cannot “prevail over the actual terms of the instrument in question”. By contrast, meeting minutes which are just “diplomatic documents recording the state of progress of the negotiations… [possess] no legally binding force”.

Greece v Turkey (Aegean Sea Continental Shelf): A joint communique can constitute a treaty.

Vienna Convention on the Law of Treaties


Arts 2(1)(a), 3: The VCLT applies only to treaties between states, not to international agreements concluded between states and other subjects of international law or between such other subjects of international law.


Kasikili/Sedudu Island Case: The VCLT applies only to its parties.

Prospective effect

Art 4: The VCLT only applies to treaties concluded after its entry into force in 1980.

Written treaties

Arts 2(1)(a), 3: The VCLT applies only to treaties “in written form… governed by international law”, not to other types of treaties such as oral agreements.

Customary international law

Arts 3, 4: The non-applicability of the VCLT in certain circumstances does not preclude the applicability of rules of customary international law.

Default nature

The VCLT can be displaced by express provision, so always examine the terms of the treaty first.

Conclusion of treaties

1. Authority to conclude treaties

Art 7: A person is considered as representing a state if: (1) he produces full powers, (2) he is considered as representing his State without having to produce full powers in virtue of his functions (e.g. Head of State, Head of Government, Minister for Foreign Affairs) or (3) he is considered as representing his State without having to produce full powers because the State intention was to consider him as representing the State and to dispense with full powers.

Art 8: Consent is ineffective if made by an unauthorised person unless later confirmed by that State.

2. Consent

Art 9: The consent of all the participating States is necessary.

Art 11: Consent may be expressed by signature, exchange of instruments constituting a treaty, ratification, acceptance, approval of accession, or by any other means if so agreed.

Art 12-17: Specific provisions on each mode.

3. Entry into force

Art 24: A treaty enters into force on the date it provides or the negotiating States agree; otherwise, a treaty enters into force as soon as consent to be bound is established for all the negotiating States.

Interim obligation

Art 18: A state is legally obliged to refrain from acts which would defeat the object and purpose of the treaty in the period between signature and ratification (if required) until it has indicated that it will not be a party to the treaty, and also in the period between consent to be bound and entry into force of the treaty, provided the latter is not unduly delayed.



Art 42(1): The grounds for invalidity set out in Arts 46-53 are exhaustive.

Art 69: An invalid treaty has no legal force.

Grounds for voidability

1. Consent expressed in violation of a provision of internal law

Art 46: (1) Consent to be bound expressed in violation of a provision of its internal law; (2) violation manifest, i.e. would have been objectively evident to any State conducting itself in the matter in accordance with normal practice and in good faith; (3) violation concerned a rule of its internal law of fundamental importance.

Eastern Greenland, Spanish Zones of Morocco Claims, Qatar v Bahrain, Cameroon v Nigeria: Arguments of...

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