A/AC.291/L.15 Parties, be submitted to arbitration. If, six months after the date of the request for arbitration, those States Parties are unable to agree on the organization of the arbitration, any one of those States Parties may refer the dispute to the International Court of Justice by request in accordance with the Statute of the Court. 3. Each State Party may, at the time of signature, ratification, acceptance or approval of or accession to this Convention, declare that it does not consider itself bound by paragraph 2 of this article. The other States Parties shall not be bound by paragraph 2 of this article with respect to any State Party that has made such a reservation. 4. Any State Party that has made a reservation in accordance with paragraph 3 of this article may at any time withdraw that reservation by notification to the Secretary-General of the United Nations. Article 64. Signature, ratification, acceptance, approval and accession [agreed ad referendum] 1. This Convention shall be open to all States for signature at United Nations Headquarters in New York until 31 December 2026. 2. This Convention shall also be open for signature by regional economic integration organizations, provided that at least one member State of such an organization has signed this Convention in accordance with paragraph 1 of this article. 3. This Convention is subject to ratification, acceptance or approval. Instruments of ratification, acceptance or approval shall be deposited with the Secretary -General of the United Nations. A regional economic integration organization may deposit its instrument of ratification, acceptance or approval if at least one of its member States has done likewise. In that instrument of ratification, acceptance or approval, such organization shall declare the extent of its competence with respect to the matters governed by this Convention. Such organization shall also inform the depositary of any relevant modification in the extent of its competence. 4. This Convention is open for accession by any State or any regional economic integration organization of which at least one member State is a Party to this Convention. Instruments of accession shall be deposited with the Secretary -General of the United Nations. At the time of its accession, a regional economic integration organization shall declare the extent of its competence with respect to matters governed by this Convention. Such organization shall also inform the depositary of any relevant modification in the extent of its competence. Article 65. Entry into force 1. This Convention shall enter into force on the ninetieth day after the date of deposit of the fortieth instrument of ratification, acceptance, approval or accession. For the purpose of this paragraph, any instrument deposited by a regional economic integration organization shall not be counted as additional to those deposited by member States of that organization. 2. For each State or regional economic integration organization ratifying, accepting, approving or acceding to this Convention after the deposit of the fortieth instrument of such action, this Convention shall enter into force on the thirtieth day after the date of deposit by such State or organization of the relevant instrument or on the date on which this Convention enters into force pursuant to paragraph 1 of this article, whichever is later. Article 66. Amendment 1. After the expiry of five years from the entry into force of this Convention, a State Party may propose an amendment and transmit it to the Secretary -General of the United Nations, who shall thereupon communicate the proposed amendment to the States Parties and to the Conference of the States Parties to the Convention for the 40/41 V.24-14137