The appropriate Government may, by notification in the Official Gazette and subject to such conditions and restrictions, if any, and for such period or periods as may be specified in the notification, direct that all or any of the provisions of this Act or the rules made thereunder shall not apply to or in relation to any establishment or class of establishments or any contractor or class of contractors or any inter-State migrant workmen in such establishment or class of such workmen, if that Government is satisfied that it is just and proper so to do having regard to the methods of recruitment and the conditions of employment in such establishment or class of establishments and all other relevant circumstances.