(1) All immovable property which purports to have been requisitioned by a State Government for any public purpose, being a purpose of the Union, under any Provincial or State Act and which, immediately before the 25th day of January, 1952 , was used or occupied by the Central Government or by an officer or authority subordinate to that Government shall, as from that date, be deemed to be property duly requisitioned under section 3 of this Act, and every such requisition shall, notwithstanding any judgment, decree or order of any court, be deemed always to have been valid as if this Act had been in force on and from the date of the requisition and the requisition had been duly made by a competent authority under this Act, and all the provisions of this Act shall apply accordingly: Provided that all agreements and awards for the payment of compensation in respect of any such property for any period of requisition before the 25th day of January, 1952 and in force immediately before that date shall be valid and shall be deemed always to have been valid and shall continue to be in force and shall apply to the payment of compensation in respect of that property for any period of requisition after that date.