Sen is said to be soft-pedalling on the issue even though EREB chairman S R Shikdar had sent a stern letter to NTPC.
The defaulting states are unable to pay the bills as these include energy consumption by Assam and Andhra Pradesh.
National Thermal Power Corporation officials, however, are exerting pressure on the power ministry to take a tough line, especially after the EREB chairman threatened to take action.
The officials are aware the three power stations