The Supreme Court on Monday reserved its order on pleas for lifting its ban on registration of diesel cars with engine capacity of 2,000 cc and above in the NCR even as the central government argued for it as while opposing imposition of any environment cess.Seeking the modification of the apex court's December 16, 2015 order, Attorney General Mukul Rohatgi urged the bench headed by Chief Justice T.S. Thakur, that "no cess should be levied by the court as the state is offering" to come back with a report on the issue.Seeking six weeks time to submit the report, he said: "I don't think it is appropriate for the court to impose a tax as it should be done under the scheme of the constitution."The central government's stand came in course of the hearing of a batch of petitions by car manufacturers including Mercedes Benz and Toyota seeking lifting of the ban on registration of big cars with an offer that it will deposit 1 per cent of such as car's cost as environment cess.