Accusing UPA government of allocating 73 coal blocks across the country free of cost to 143 private companies between 2006-09 when the Coal Ministry was with the Prime Minister, BJP MP Hansraj Ahir claimed this had led to a loss of Rs 85,000 Crore to the exchequer.

"Government introduced Mines and Minerals (Amendment) Bill in 2006, which proposed auction in place of free allotment on First-Cum-First-Served-User basis. The rush followed and the government, which should have stopped the allotments till the successful passage of the Bill, instead surreptitiously gifted coal blocks to the private parties in the interregnum," Ahir said.

"BJP demands an immediate Supreme Court-monitored inquiry and a special audit by CAG, into the Coal Scam," BJP spokesperson Prakash Javadekar said.

17 billion metric tonnes (BMT) of coal reserves worth Rs 51 Lakh Crore were allotted in these four years before the Bill was passed, Ahir said.

"51 companies were allotted coal blocks in 2006, 19 companies in 2007, 41 companies in 2008 and 32 companies in 2009. The going rate, as alleged by the business circles, is Rs 50 per metric tonnes. Thus, more than Rs 85,000 crore changed hands during the four-year coal scam," he said.

Shibu Soren had resigned as Coal Minister in 2006 and the Prime Minister kept the porfolio with him till 2009 when Sri Prakash Jaiswal was given the charge of the ministry.

"BJP demands explanation from the Prime Minister about this loot of precious natural resources, as the culpability of the Prime Minister is clearly established," Ahir said.

The main opposition will raise this issue in Parliament during the forthcoming Monsoon session.

"The modus operandi of the 2G scam with this Coal scam seems to be similar. Rules were bent, definitions were changed, modalities were distorted to benefit the allottees. Illegal gratification was obtained by using the aforementioned Bill as an instrument," Ahir said.

Making further comparisons with the 2G scam, the BJP MP said many of the allottees sold their allotted coal blocks to other companies at a hefty premium.

"Only 2 out of these 143 companies' allotments have actually started production. BJP demands immediate cancellation of nearly 90 private companies coal blocks whose time limit for commencement of production has lapsed," Ahir said.