If any land, in respect of which the payment of a betterment fee has been accepted in pursuance of sub-section (3) of section 161 or has been made after its determination under section 162 or in respect of which an agreement in regard to the betterment fee has been executed under section 166, be subsequently required for any of the purposes of this Chapter the payment or agreement shall not be deemed to prevent the acquisition of the land in pursuance of a fresh declaration published under section 6 of Land Acquisition Act, 1894.