2.4 Entry into force

The Ottawa treaty entered into force, that is, became binding international law, on 1 March 1999. For that to happen, 40 States had to deposit an instrument of ratification with the Secretary-General of the United Nations as notification of their consent to be bound by the treaty. The 40th ratification was submitted by Burkina Faso in September 1998 and, in accordance with Article 17, the treaty entered into force six months later and will apply indefinitely.

States which have the treaty signed but not yet submitted an instrument of ratification to the UN Secretary-General are not bound by its provisions. A State’s signature is not of itself enough to bind the signatory to respect all of its provisions. Signing a treaty does, however, signal the intention to adhere formally at a later date (through ratification, approval or acceptance) and international law requires that a signatory must not do anything that undermines the “object and purpose” of the treaty. The two-stage process of signature followed by formal adherence is intended, for instance, to allow national parliaments or legislatures to debate the treaty and its implications for the country before a final decision is made whether or not to become bound by its provisions.

Following its entry into force on 1 March, the Ottawa treaty is no longer open for signature. Nonetheless, countries which have not signed it may still formally adhere to it by a one stage process called accession. Any State may accede directly to the treaty in place of signature and ratification, thereby binding itself to respect its provisions.