Nothing contained in this Act shall preclude the Central Government from calling for and examining, on its own motion, if it considers it necessary so to do in the public interest, any case in which a decision has been made by the Commission under section 12 but no appeal lies thereto, and passing such order thereon as it thinks fit:
     Provided that no such order shall be made prejudicially affecting any person except after giving him an opportunity of making a representation in the matter.