(1) The Secretary of State shall before the end of the year 1972—
(a) make payments to the British Railways Board amounting in all to £27 million, . . .
(b) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
and any such payment shall be made out of money provided by Parliament and shall be for the credit of the revenue account of the body to which it is made.
(2) Subject to the preceding provisions of this section, the time at which the payments are made, and the amount paid at any one time, shall be such as the Secretary of State may, with the consent of the Treasury, determine.