law: 92. Prior sanction of Central Government to charge expenditure to capital.-
  (1) No expenditure shall be charged by a Board to capital without the previous sanction of the Central Government:
  Provided that a Board may without such sanction charge to capital expenditure not exceeding such limit as may be specified, and subject to such conditions as may be imposed, by the Central Government.
  (2) Nothing in sub-section (1) shall be deemed to require the further sanction of the Central Government in any case where the actual expenditure incurred as a charge to capital exceeds the expenditure sanctioned in this behalf by the Central Government unless the excess is more than ten per cent. of the expenditure so sanctioned.