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1. Any Contracting Party may propose one or more amendments to this Convention. The text of any proposed amendments shall be transmitted to the Secretary-General of the United Nations who shall transmit it to all Contracting Parties and inform all other countries referred to in article 12, paragraph 1.
2. Any proposed amendment circulated in accordance with the preceding paragraph shall be deemed to be accepted if no Contracting Party expressed an objection within a period of six months following the date of circulation of the proposed amendment by the Secretary-General.
3. The Secretary-General shall, as soon as possible, notify all Contracting Parties whether an objection to the proposed amendment has been expressed. If an objection to the proposed amendment has been expressed, the amendment shall be deemed not to have been accepted and shall be of no effect whatever. If no such objection has been expressed the amendment shall enter into force for all Contracting Parties three months after the expiry of the period of six months referred to in the preceding paragraph.
4. Independently of the amendment procedure laid down in paragraphs 1, 2 and 3 of this article, the annexes to this Convention may be modified by agreement between the competent Administrations of all the Contracting Parties. The Secretary-General shall fix the date of entry into force of the new texts resulting from such modifications.