Labour has demanded that members appointed to the new fiscal watchdog be subject to confirmation hearings before MPs as part of moves to make it more accountable.
Shadow chancellor Alistair Darling said the deliberations of the newly created Office for Budget Responsibility (OBR) should be “completely open and transparent”.
His call for greater openness followed a grilling of the OBR’s interim chairman, Sir Alan Budd, by MPs on the Treasury Select Committee, who accused him of “naivety” in his handling of forecast figures.
Sir Alan, 73, said there was “no conspiracy or pressure” from the Treasury and denied any disagreement with George Osborne was behind his decision to leave after just three months in the job.
The OBR - set up by the Chancellor to re-establish confidence in the official economic forecasts - has been mired in controversy since it emerged it tweaked employment predictions ahead of the 22 June Budget and had also released crucial figures just minutes before Prime Minister’s Questions.
At question time in the Commons, Mr Darling said the independence and credibility of the OBR was “absolutely paramount”.
He asked Chief Secretary to the Treasury Danny Alexander: “Would it not be better if the OBR was more accountable to this House, with its appointments being subject to confirmation hearings by the Treasury Select Committee and its deliberations should be completely open and transparent?
“What we have at the moment is a situation where a good idea has been strangled at birth by the way in which this government has been treating it.”
Mr Alexander replied: “The independence of the OBR is not in question. That was made clear by Alan Budd in his evidence today.
“This was a good idea brought forward by this government, it will be established in legislation.
“I don’t think it was even part of the former Chancellor’s secret plans before the election alongside a rise in VAT, a cut in corporation tax and a cut in income tax.
“Those are measures that you should be supporting in this Budget, that you came up with in the first place.”