Section 335(3) in The New Delhi Municipal Council Act, 1994
(3)If the Chairperson fails to acquire the land within a period of six months from the receipt of the notice, the improvement scheme shall have effect after the expiration of the said six months as if the land were not designated as subject to acquisition by the Chairperson or were not designated as subject to acquisition by the Chairperson or were not required to be kept as an open space.