(1) In this section and in sections 10, 11, 12 and 14 the word "plan" means the master plan as well as the zonal development plan for a zone.
     (2) Every plan shall, as soon as may be after its preparation, be submitted by the Authority to the Central Government for approval and that Government may either approve the plan without modifications or with such modifications as it may consider necessary or reject the plan with directions to the Authority to prepare a fresh plan according to such directions.