The Town and Country Planning (General Permitted Development) Order 1995

A.2    Conditions

Development is permitted by Class A subject to the conditions that, when the operations have been carried out—

(a)any building, structure, works, plant or machinery permitted by Class A shall be removed, and

(b)any adjoining land on which development permitted by Class A has been carried out shall, as soon as reasonably practicable, be reinstated to its condition before that development was carried out.