New Delhi, Apr 24 (PTI): Unfazed by the Opposition attack, Congress President Sonia Gandhi Tuesday dismissed the demand for the resignation of Prime Minister Manmohan Singh over the coalgate issue.

"Let them ask" was the terse response of Gandhi when approached by reporters on the issue after a meeting of the Congress Core Group headed by her.

The meeting of the Core Group was convened immediately after both Houses were adjourned over the issue for half an hour in the morning.

The meeting, which was also attended by Parliamentary Affairs Minister Kamal Nath discussed the strategy ahead in wake of the Opposition reviving its attack on the government on the coalgate issue and bringing the Prime Minister as well under the target.

Kamal Nath alleged that the BJP was using "diversionary politics by trying to draw the attention away from core issue."

"In the last nine years, the BJP has demanded the Prime Minister's resignation many many times. And there is no basis to this. The BJP is using diversionary politics by trying to draw the attention away from core issue," Nath said.

Keeping up the heat on the government, BJP today demanded resignation of Prime Minister on the coalgate issue.

Gandhi had yesterday also given an indication of the aggression in Congress' response to the Opposition's charges.

In the Lok Sabha today, soon after Speaker Meira Kumar made a reference to Panchayati Raj Day, opposition members rushed to the Well raising slogans and waving placards on various issues.

BJP members rushed to the Well demanding resignation of the Prime Minister over the issue of coal block allocations. Shouting slogans, they also demanded dismissal of Law Minister Ashwani Kumar who is alleged to have vetted the CBI report to the Supreme Court.