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1. If either of the Contracting Parties considers it desirable to modify any provisions of the present Agreement and/or its Annex, it may request consultations with the other Contracting Party. Such consultations, which may be between the respective Aeronautical Authorities and which may be through discussion or by correspondence, shall begin within a period of sixty (60) days from the date of the request.
2. Any modifications of the present Agreement decided upon during the consultations referred to in paragraph 1 above, shall be agreed upon in writing between the Contracting Parties and shall take effect on the date on which the Contracting Parties have informed each other in writing that the formalities constitutionally required therefor in their respective countries have been complied with.
3. The respective Aeronautical Authorities are entitled to agree in writing to any modifications of the Annex to the present Agreement. Such modifications shall take effect on a date to be determined by an exchange of diplomatic notes.