Artikel 15

(1). Not less than twenty-five per cent (25 %) of the Contracting States shall be entitled, by request addressed to the International Civil Aviation Organization given not earlier than twelve months after the entry into force of this Agreement, to call for a meeting of Contracting States in order to consider any amendments which it may be proposed to make to the Agreement. Such meeting shall be convened by the International Civil Aviation Organization, in consultation with the President of the European Civil Aviation Conference, on not less than three months' notice to the Contracting States.
(2). Any proposed amendment to the Agreement must be approved at the meeting aforesaid by a majority of all the Contracting States, two-thirds of the Contracting States being necessary to constitute a quorum for the purpose of holding the meeting.
(3). The amendment shall enter into force in respect of States which have ratified such amendment when it has been ratified by the number of Contracting States specified by the meeting aforesaid, or at such time thereafter as may have been specified by the meeting.