Article 17 1. This Protocol shall be open for signature by any State that has signed, acceded to or ratified the Convention. 2. This Protocol shall be subject to ratification by any State that has ratified or acceded to the Convention. Instruments of ratification shall be deposited with the Secretary-General of the United Nations. 3. This Protocol shall be open to accession by any State that has ratified or acceded to the Convention. 4. Accession shall be effected by the deposit of an instrument of accession with the Secretary-General of the United Nations. Article 18 1. This Protocol shall enter into force three months after the date of the deposit with the Secretary-General of the United Nations of the [fifth] [tenth] [twentieth] instrument of ratification or accession. 2. For each State ratifying this Protocol or acceding to it after its entry into force, this Protocol shall enter into force three months after the date of the deposit of its own instrument of ratification or accession. Article 20 [No reservations to this Protocol shall be permitted.] Alternative [Reservations to this Protocol shall be permitted, unless such a reservation is incompatible with the object and purpose of the present Protocol and the Convention, in accordance with the rules of international law.] Article 21 1. Any State Party to the present Protocol may propose any amendment and file it with the Secretary-General of the United Nations. The Secretary-General shall thereupon communicate any proposed amendments to the States Parties to this Protocol with a request that they notify her/him whether they favour a conference of States Parties for the purpose of considering and voting on the proposal. In the event that at least one third of the States Parties favour such a conference, the Secretary-General shall convene the conference under the auspices of the United Nations. Any amendment adopted by a majority of the States Parties present and voting at the conference shall be submitted to the General Assembly of the United Nations for approval. 2. Amendments shall come into force when they have been approved by the General Assembly of the United Nations and accepted by a two-thirds majority of the States Parties to this Protocol in accordance with their respective constitutional processes. -84-