With the figure of Rs 1.76 lakh crore loss in 2G spectrum allocation being disputed within, CAG Vinod Rai on Monday offered to give explanation on it to the Parliament's Public Accounts Committee which is set to re-examine the case in view of demand by a Congress member.

The PAC, which met here to discuss the CAG reports on Commonwealth Games and Adarsh Society scams, also decided to summon R P Singh, former Director General of Audit (Post and Telecommunications), who was the lead auditor in 2G spectrum allocation and had reportedly disputed the loss figure of Rs 1.76 lakh crore.

The decision was taken after Congress member Sanjay Nirupam demanded that Singh should be called to explain, sources said.

Hours ahead of the PAC meeting, the Committee Chairman Murli Manohar Joshi also received a letter from Rai who expressed readiness to explain the methodology used for estimating the losses due to the controversial allocation of 2G radiowaves.

Rai cited Nirupam's letter to Joshi, which had appeared in a section of the media, pointing out reported differences within the CAG on the estimation of the losses.

Singh had reportedly said the losses were to the tune of Rs 2,645 crore only.

It was also decided that Rai's deputy Rekha Gupta would also be present to explain the doubts of the members.

Nirupam is understood to have questioned the credibility of all the CAG reports and insisted that the Committee should not proceed further on the auditor's reports on Commonwealth Games and Adarsh Society scam till the issue of estimation of 2G losses was settled.

Interestingly, Congress members Jagdambika Pal and Saifuddin Soz were learnt to have pacified Nirupam and urged him to allow the Committee to proceed with examining officials from various departments on the alleged irregularities in the conduct of the Games and the Adarsh society issue.

A member pointed out that R P Singh had himself made a presentation on the CAG estimation of Rs 1.76 lakh crore loss in 2G scam before the Committee a few months back.

Sources said that Singh could be asked to explain why did he stand by the Rs 1.76 lakh crore figure while making the presentation before the Committee, when he had a different view and whether the Committee was misguided.

Another member said the Committee would like to know whether Singh stood by media reports on differences within the CAG on estimation of losses.

The Committee is also learnt to be mulling asking publications which carried the news on whether there was any denial or an alternative version offered to the reports on the differences.

BJP member Prakash Javadekar and Nirupam were understood to have entered into a verbal duel over the credibility of CAG reports.

Javadekar is learnt to have suggested that all those who have spoken anything on the estimated losses, including Telecom Minister Kapil Sibal, former Telecom Minister A Raja, and TRAI officials, should also be called to give their views on the issue.

The BJP member said that even the Rs 2645 crore loss was a huge amount and the claims of the opposition that government exchequer lost money stood vindicated.