"The CAG should reconsider how far its estimate was right with regard to the report, which it had earlier given and the losses that it had computed (in spectrum allocation two years ago)," Singh said.
The remarks came a day after the the much-talked about 2G spectrum auction yesterday virtually flopped, yielding just Rs9,407 crore contrary to the high valuation estimated by the CAG in its damning report two years ago.
Singh also sought to dismiss the suggestion that the auction yielding less revenue this time is a reflection of disenchantment of telecom companies with the government.
The government was targeting a minimum of Rs28,000 crore from the sale of 2G spectrum in the GSM band and the tepid response may upset its efforts to meet the revised fiscal deficit target of 5.3% of GDP.
Overall, the government had budget Rs40,000 crore as revenue from spectrum sale this fiscal.
The Comptroller and Auditor General had in 2010 said the then telecom minister A Raja's decision to give away spectrum at rates fixed in 2001 had caused a presumptive loss of Rs1.76 lakh crore to the exchequer.
Telecom minister Kapil Sibal had refused yesterday to comment on the CAG's estimation of Rs1.76 lakh crore as the loss to the exchequer in giving away spectrum on first-come-first-serve basis in 2008.
In an apparent dig at the CAG, he had merely said, "the facts are before the nation and quite clear."