Try Article 151 Para (3)
Permission required where pilot’s licence does not meet relevant minimum standards
151.—(1) This article applies to any pilot’s licence, other than a Part-FCL licence, endorsed to the effect that the holder does not satisfy in full the relevant minimum standards established under the Chicago Convention.
(2) The holder of such a licence, which has been granted or rendered valid under this Order, must not act as a member of the flight crew of an aircraft registered in the United Kingdom in or over the territory of a Contracting State other than the United Kingdom, except in accordance with a permission granted by the competent authority of that State.
(3) The holder of a pilot’s licence, which has been granted or rendered valid under the law of a Contracting State other than the United Kingdom, must not act as a member of the flight crew of any aircraft in or over the United Kingdom except in accordance with a permission granted by the CAA, whether or not the licence is rendered valid under this Order.