New Delhi, Dec 22 (IANS) The National Democratic Alliance (NDA) Wednesday sought Prime Minister Manmohan Singh's resignation "on moral grounds" if the government fails to answer opposition concerns on the alleged irregularities in the 2G spectrum allocation.

"If you are saying the prime minister's post should be above suspicion, then you should honestly form a JPC (joint parliamentary committee) to probe the 2G scam. And if you don't have answers to opposition concerns, then the prime minister should quit his post on moral grounds," Arun Jaitley of the Bharatiya Janata Party (BJP), which leads the NDA, said while addressing an anti-government rally here.

At the Congress plenary Monday, Manmohan Singh had again rejected the BJP's demand to set up a JPC to investigate the 2G scam. He expressed his readiness to appear before parliament's Public Accounts Committee but said the prime minister's post should be above suspicion. The opposition has turned down the offer.

The BJP and its partners in the National Democratic Alliance (NDA) took its fight against corruption to Delhi's streets two days after the Congress plenary concluded.

All major leaders of the NDA constituents are attending the rally at the Ram Lila grounds.

The anti-United Progressive Alliance (UPA) rally comes after the opposition parties stalled parliament for the entire Nov 9-Dec 13 winter session demanding a JPC probe into the wrongdoings in the allocating second generation telephony spectrum in 2008, an issue that forced DMK leader A.Raja to quit as communications minister.

The rally, targetting the Congress-led UPA on various corruption scams, kick-starts the NDA's two-month long nationwide campaign against corruption.