4.—(1) In any case where a prospective apportionment is to be made by arbitration, an arbiter shall be appointed by agreement between the occupier and any other interested party or, in default of agreement, by the Scottish Ministers on an application by the occupier.
(2) Where an arbiter is appointed by agreement in terms of sub-paragraph (1), the occupier shall give notice of the appointment of the arbiter to the Scottish Ministers within fourteen days from the date of the appointment.