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The government is again being urged by business leaders to push ahead with airport expansion.

The calls came after an influential group of MPs opened the door to further delays by calling for more economic analysis of the costs and benefits of additional runways.

It emerged that Treasury Committee chairman Andrew Tyrie attacked the Airports Commission, saying the Treasury needed to “go further” to make the economic case for more capacity.

In a letter to chancellor George Osborne, he reportedly said: “The robustness of the Airports Commission’s conclusions cannot be determined from the information available in the Davies report.

“Without adequate information on the robustness of the economic case, parliament and the public will not be able to judge the merits of any decision. Decisions of such crucial economic importance cannot be left to the Department for Transport,” Tyrie added. “So the chancellor of the exchequer should take the lead.”

A Treasury spokesperson declined to comment, but a transport department spokesman said the government would respond to the letter “as soon as possible”, adding: “The case for aviation expansion is clear – and it’s vitally important we get the decision right.”

Meanwhile, Sir Howard Davies, who led the Airports Commission and now chairs Royal Bank of Scotland, rejected Tyrie’s claims.

He told City A.M.: “I think many will be surprised at the suggestion that there was insufficient detail in what was a very lengthy report.”

Davies added “while it would be possible” to carry out the extra analysis Tyrie requested, “there would be little value added” by doing so, and the Airports Commission’s ultimate recommendation “would not be changed”.

The commission recommended building a third runway at Heathrow last July. The government responded in December by saying it would again postpone making a decision on whether to expand the west London airport until at least the summer.

But now industry groups are hitting out at Tyrie.

“The Airports Commission spent three years analysing impartial evidence, at a cost of £20m,” Rhian Kelly from the Confederation of British Industry said. “We cannot fall into the habit of unpicking this evidence delaying further the government taking tough decisions.”

John Dickie, director of strategy and policy at London First, told City A.M.: “MPs should of course see the case for airport expansion. But we must not confuse transparency with calls for further studies.

“We’ve spent decades debating airport expansion, the Airports Commission has spent three years reaching its recommendations, and now we need a decision,” Dickie added. “Further delay will cause real damage to our economy.”

WPP chief executive Sir Martin Sorrell told the newspaper: “Sadly, this looks like yet another possible delay in solving a major competitive infrastructure issue.”