(1) Notwithstanding any thing contained in any other law for the time being in force, but subject to the provisions of sub section (3) of section 5 and sub section (4) of section 10, no person shall transfer by way of sale, mortgage, gift, lease for a period exceeding ten years, or otherwise, any urban or urbanisable land with a building (whether constructed before or after the commencement of this Act) or a portion only of such building for a period of ten years of such commencement or from the date on which the building is constructed, whichever is later, except with the previous permission in writing of the competent authority." Inter alia, the aforesaid provision is clearly applicable to a building or a portion of such building which would include a flat therein standing on any urban or urbanisable land falling within the permissible ceiling area which a holder of a vacant land is entitled to retain with himself and under this provision any transfer of such property by way of sale, mortage, gift or lease for ten years or otherwise, is prohibited for the period of ten years from the commencement of the Act except with the previous permission in writing of the competent authority.