, a vacancy resulting from the disqualification, death, incapacity or resignation of an arbitrator shall be promptly filled by the same method by which his appointment had been made.
(2) In addition to filling vacancies relating to arbitrators appointed by him,the Chairman shall:
a)
fill a vacancy caused by the resignation, without the con- sent of the Tribunal,of an arbitrator appointed by a party; or
b)
at the request of either party, fill any other vacancy, if no new appointment is made and accepted within 45 days of the notification of the vacancy by the Secretary-General.
(3) In filling a vacancy the party or the Chairman,as the case may be, shall observe the provisions of these Rules with respect to the appointment of arbitrators.