The party also questioned its remit to audit the accounts of private companies and sought to debunk the argument that the government should have gone for the auction route.
Quoting a Supreme Court order in April this year, party spokesperson Manish Tewari said the CAG can audit any private company only if asked by the government to do so.
"From where did the CAG get the authority to audit the private companies, which got coal, and arrived at an estimate? There are a large number of unanswered questions with regard to not only the methodology of the audit but whether CAG could have at all conducted the audit," Tewari said.
Seeking a response to the "many questions" raised by the report, he told the CAG "to say that we will not join the issue in public won't do. When you have triggered a debate in the country through your estimates, you will have to answer regarding the process and working style adopted by you".
At the same time, he ruled out any possibility of the impeachment of the CAG. "You have to make a distinction between the CAG and its report. We are disputing the report of the CAG and the methodology he has adopted."
Replying to questions, Law Minister Salman Khurshid, who was also fielded by the party, said the issue of loss has not been taken up by the CAG report and its findings merely said someone gets the benefit because of the absence of a particular policy for coal allocation.
"I do not think anyone has talked about loss to the government. The issue of loss has not been taken by the CAG at all," he said.