New Delhi: The Supreme Court has directed that the Eastern Peripheral Expressway, meant to decongest Delhi's traffic and reduce air pollution, should be opened to the public from June 1 whether or not the Prime Minister can inaugurate it by then.

"Why don't you open it and inaugurate it later? The high court of Meghalaya is functioning for the past five years without a formal inauguration," Justice Madan B. Lokur told counsel for the National Highway Authority of India, which has built the Rs 11,000-crore road.

The court was annoyed when amicus curiae (friend of the court) Aparajita Singh said no steps had been taken to open the highway to regular traffic despite additional solicitor-general A.S. Nadkarni's assurance at the last hearing about an April 29 inauguration.

To a query from the court, counsel for the NHAI said the delay was on account of Prime Minister Narendra Modi's busy schedule.

He said the NHAI had sought time from the Prime Minister's Office for an inauguration this month but was yet to receive a confirmation.

"You cannot pass the buck saying the PM is not available," Justice Lokur, sitting on the bench with Justice Deepak Gupta, said. "A delay is not in the interest of the people of Delhi."

The bench then asked the NHAI to take steps to inaugurate the highway on or before May 31, failing which it should be opened to the public from June 1.

"I'm sure (that) even the Prime Minister will agree to it," the amicus said, prompting Justice Lokur to joke: "How do you know it? Do you have some inside information about the PMO?"

The court was hearing a petition from eminent environmentalist M.C. Mehta, who has sought anti-pollution measures in Delhi