12.—Every order under section 4 or regulation made by the Minister under this Act shall be laid before each House of the Oireachtas as soon as may be after it is made and, if a resolution annulling the regulation is passed by either such House within the next subsequent 21 days on which that House has sat after the regulation is laid before it, the regulation shall be annulled accordingly but without prejudice to the validity of anything previously done thereunder.