18.—(1) Except where otherwise provided, the provisions of this Order are to be executed and enforced by the local authority.
(2) The National Assembly for Wales or the Secretary of State may direct, in relation to cases of a particular description or any particular case, that an enforcement duty imposed on a local authority under this article is to be discharged by the National Assembly for Wales or the Secretary of State (as the case may be) and not by the local authority.