The
Vienna Convention considers the invalidity of a treaty being claimed by one or more parties, but contested by other States Parties as the most likely case for a dispute settlement (Article 65 (3)). Since the
Vienna Convention does not intend to be prejudicial to other dispute settlement mechanisms which might have been agreed upon between the States (Article 65 (4)), it expresses its preference for a dispute settlement through one of the means listed in Article 33 of the
Charter of the United Nations, i.e.
- negotiation,
- enquiry,
- mediation,
- conciliation,
- arbitration,
- judicial settlement,
- resort to regional agencies or arrangements
- or other peaceful means of their own choice
In the special case of a dispute concerning the issue of a conflict between a treaty on one hand and a peremptory norm of general international law on the other (
jus cogens, see Articles 53 and 64), the
Vienna Convention, as a recourse of last resort, provides for the mandatory settlement of the dispute by the
International Court of Justice. Of course, the States Parties can also submit such a dispute by common consent to arbitration (Article 66 (a)).
Any other dispute concerning the invalidity, the termination or the suspension of a treaty can, upon a request addressed to the
Secretary-General of the United Nations, be submitted to the conciliation commission foreseen in the
Annex to the Vienna Convention (Article 66 (b)). Three out of the five conciliators constituting the conciliation commission must be chosen by the parties from a list held by the Secretary-General. Until today, the conciliation commission has not entered into function.
