Where a request for a copy of the application whose priority is claimed in the international application is made under Rule 43bis.1(b) by the International Searching Authority or, under Rule 66.7(a), by either the International Searching Authority, or the International Preliminary Examining Authority before the International Bureau has received the priority document under Rule 17.1, the International Bureau shall, unless the applicable time limit referred to in Rule 17.1(a) has already expired, inform the applicant of such request and remind him of the requirements of Rule 17.1.