27. The Government may from time to time, by notification published in the official Gazette,-(a) exempt any person by name or in virtue of his office, or any class of persons, or exclude any description of arms or ammunition, or withdraw any part of ¹[Bangladesh], from the operation of any prohibition or direction contained in this Act; and (b) cancel any such notification, and again subject the persons or things or the part of Bangladesh ²[* * *] comprised therein to the operation of such prohibition or direction .