3.
Subject to Article 12 of this Order, the like privileges and immunities as are conferred on consular officers and on members of their families forming part of their households by section 1 of the Act read with Section II of Chapter II in Schedule 1 to the Act shall be conferred.
(a)
on persons for the time being holding any of the offices or an office in any of the classes of office specified in Schedule 1 to this Order, and on members of their families forming part of their households, and
(b)
on members of the staff of any such officer as is mentioned in paragraph (a) of this Article who appear to the Secretary of State to perform duties substantially corresponding to duties which, in the case of a foreign sovereign Power, would be performed by a consular officer, and on members of their families forming part of their households.