The Minister may authorise the council of any county F1, county boroughF2or metropolitan district . . . F3 to exercise on his behalf any of the powers (other than the power to make regulations) conferred on him by this Act; and where a council is so authorised subsection (1) of section four of this Act shall have effect in relation to land in the county F1, county boroughF2or metropolitan district . . . F3 in question as if the reference therein to a person authorised by the Minister included a reference to a person authorised by the council.