Article 18 Vienna Convention on the Law of Treaties
Obligation not to defeat the object and purpose of a treaty prior to its entry into force
A State is obliged to refrain from acts which would defeat the object and purpose of a treaty when:
(a) it has signed the treaty or has exchanged instruments constituting the treaty subject to ratification, acceptance or approval, until it shall have made its intention clear not to become a party to the treaty; or
(b) it has expressed its consent to be bound by the treaty, pending the entry into force of the treaty and provided that such entry into force is not unduly delayed.
See also: Article 17 Vienna Convention on the Law of Treaties
