(1) If the parties have not agreed upon the number of arbitrators and the method of their appointment within 60 days after the registra- tion of the request, the Secretary-General shall, upon the request of either party promptly inform the parties that the Tribunal is to be con- stituted in accordance with the following procedure:
a)
either party shall,in a communication to the other party:
(i)
name two persons,identifying one of them,who shall not have the same nationality as nor be a national of either party,as the arbitrator appointed by it,and the other as the arbitrator proposed to be the President of the Tribunal;and
(ii)
invite the other party to concur in the appointment of the arbitrator proposed to be the President of the Tri- bunal and to appoint another arbitrator;
b)
promptly upon receipt of this communication the other party shall,in its reply:
(i)
name a person as the arbitrator appointed by it, who shall not have the same nationality as nor be a national of either party;and
(ii)
concur in the appointment of the arbitrator proposed to be the President of the Tribunal or name another person as the arbitrator proposed to be President;and
c)
promptly upon receipt of the reply containing such a pro- posal, the initiating party shall notify the other party whether it concurs in the appointment of the arbitrator proposed by that party to be the President of the Tribunal.
shall be made or promptly confirmed in writing and shall either be transmitted through the Secretary-General or directly between the parties with a copy to the Secretary-General.