At this juncture it may be mentioned that Act 37 of 1986 has further amended the 1951 Act and substituted section 4A by the following section, which insofar as it is relevant for our present purposes reads as follows: "4A (1) Where the Central Government, after consultation with the State Government, is of opinion that it is expedi ent in the interest of regulation of mines and mineral development, preservation of natural environment, control of floods, prevention 'of pollution, or to avoid danger to public health or communications or to ensure safety of buildings, monuments or other structures or for conservation of mineral resources or for maintaining safety in the mines or for such other purposes, as the Central Government may deem fit, it may request the State Government to make a premature termination of a prospecting licence or mining lease in respect of any mineral other than a minor mineral in any area or part thereof, and, on receipt of such re quest, the State Government shall make an order making a premature termination of such prospecting licence or mining lease with respect to the area or any part thereof.