The Central Government may, by notification in the Official Gazette, direct that all or any of the powers which may be exercised by it under section 7, or section 8, or both, shall, in such circumstances and under such conditions, if any, as may be specified in the notification, be exercised also by any State Government and the State Government may, with the previous approval of the Central Government, by order in writing, direct that any power which has been directed to be exercised by it shall, in such circumstances and under such conditions, if any, as may be specified in the direction, be exercised by any person subordinate to the State Government as may be specified therein.