Sch 18 para 5
(1) A Minister of the Crown may by order amend this Schedule so as to add, vary or omit an exception to section 149. (2) But provision by virtue of sub-paragraph (1) may not amend this Schedule— (a) so as to omit an exception in paragraph 3; (b) so as to omit an exception in paragraph 4(1) so far as applying for the purposes of paragraph 4(2)(a) to (e) or (3); (c) so as to reduce the extent to which an exception referred to in paragraph (a) or (b) applies.