This is apparently going to be a stormy week for the Parliament as main opposition party BJP has warned that it would stall both Houses on the infamous coal scam issue.

Demanding Prime Minister Manmohan Singh's resignation, BJP said the prime minister was morally, politically and personally responsible for the Rs 1.86 lakh crore loss estimated by the Comptroller and Auditor General (CAG) in coal block allocation.

Top leaders of BJP held a gathering at senior leader LK Advani's residence late Monday evening and discussed what strategy they should adopt in Parliament on the reported coal blocks allocation scam.

BJP said they would not let both Houses of Parliament to function until Prime Minister Manmohan Singh resigns as he was legally responsible for the loss because the coal portfolio was under his possession at the time of allotment of the coal blocks.

Speaking on the topic, BJP spokesman Ravi Shankar Prasad said, "The Prime Minister needs to introspect and resign because he was himself the Coal Minister for most of the period the allocation of coal blocks was done."

In its report, the CAG said that blocks with nearly forty-four billion tonnes of coal were allotted to private companies at throwaway prices during the tenure of Manmohan Singh as Coal Minister. In addition, a total of 194 coal blocks were allotted to private companies on mere recommendations.