(1) A lessee shall pay to the Central Government, every year, fixed rent in respect of the area covered under the production lease, at the rate for the time being specified in the Second Schedule:
     Provided that where the lessee becomes liable under section 16 to pay royalty for any mineral removed or ¹[consumed from the area] covered under such lease, he shall be liable to pay either such royalty or the fixed rent in respect of that area, whichever is greater.
     (2) The Central Government may, by notification in the Official Gazette, amend the Second Schedule so as to enhance or reduce the rate at which fixed rent shall be payable in respect of any area covered under a production lease and such enhancement or reduction shall take effect from such date as may be specified in the notification:
     Provided that the Central Government shall not enhance the rate of the fixed rent more than once during any period of three years.