The impasse in Indian Parliament continued for the third day in a row on Thursday, with the main opposition Bharatiya Janata Party (BJP) demanding Prime Minister Manmohan Singh's resignation over coal scandal.

Both Houses of Parliament -- the Lok Sabha (Lower House) and the Rajya Sabha (Upper House) -- were adjourned by Speaker Meira Kumar and Vice President Hamid Ansari respectively after BJP members called on the prime minister to quit over a recent report by the government auditor that the country lost 33 billion U.S. dollars by selling coalfields cheaply without auction between 2005 and 2009.

The independent Comptroller and Auditor General of India has, however, exonerated Singh who was also holding the Coal Ministry then, during the ruling United Progressive Alliance's first five- year term from 2004 to 2009.

Senior BJP leader Arun Jaitley said the 79-year-old Singh should accept "personal responsibility" for the coal scam and resign from his post. "The way forward is that the prime minister must accept his culpability. The reason is very obvious. For five out of the eight years (analyzed by the auditor)... he himself was the Coal Minister," he added.

The ruling Congress party, however, defended Singh -- who has also offered to make a statement over the scam -- and rejected Comptroller and Auditor General's findings as a bizarre accounting exercise, even though the BJP strongly stuck to its demand that nothing short of the Prime Minister's resignation would pacify them.

"The prime minister's image is very clean. Nobody turns (into) an accused or delinquent only by BJP's allegation," Congress spokesman Rashid Alvi said.

Highly placed sources said that Congress President Sonia Gandhi Thursday met a group of party Members of Parliament and asked them not to be on the defensive about the BJP's demand for the prime minister's resignation over the government auditor's report on coal allocation.

Charging the BJP, Parliamentary Affairs Minister Pawan Kumar Bansal said the opposition party was "running away" from Parliament and avoiding a debate on the issue. "Had the House been running, there would have been a fruitful discussion. They are working as part of a pre-decided strategy to avoid a discussion on the issue," he told the media in the national capital.

Law Minister Salman Khurshid also slammed the BJP, saying, "if they raised a question, they should have the patience to listen to the answer. Why are they scared of a discussion on the issue."

India is one of the world's largest coal producers.

The government auditor had unearthed another major scam in 2010 when it pointed out irregularities in the allocation of 2G spectrum to telecom companies at throwaway prices. The watchdog claimed that the telecom scandal caused a loss of 40 billion U.S. dollars to the exchequer. Then Telecom Minister A. Raja was compelled to resign over the scam which also rocked Parliament at the time.