The Said Business School in Oxford is at the centre of a political storm , after allegations that Prime Minister Tony Blair helped force through the plans for the £40m project.

Oxford West and Abingdon Liberal Democrat MP Dr Evan Harris claimed leaked documents showed that Downing Street put pressure on civil servants to speed up a decision on plans to build the school on the site of the former LMS railway station.

The Shadow Cabinet was tabling a series of Parliamentary questions over what he called "another murky episode in Government preferential treatment".

Downing Street denied that the Prime Minister or his officials had intervened.

The school - part of Oxford University - is named after the Syrian-born millionaire Wafic Said who backed the project with a £20m donation.

The chairman of the school's trustees is Charles Powell, brother of Jonathan Powell, Mr Blair's chief of staff.

The planning application involved the dismantling of the Grade II listed Rewley Road railway station, which has been reconstructed at the Buckinghamshire Railway Centre at Quainton, near Bicester.

According to Dr Harris, a leaked memo suggests the Prime Minister's office intervened to stop the application going to a lengthy inquiry.

The memo from south-east regional planning official Avis Gerry to planning minister Nick Raynsford followed a complaint by Dr Harris that he had not been told of the decision not to go to an inquiry, despite expressing an interest.

The memo said civil servants were "under pressure from the Prime Minister's office not to delay the decision".

Dr Harris said: "The Prime Minister's involvement means this is either control freakery taken to the extreme, a sudden interest in old railway buildings or something more suspicious.

"The issue is not whether the school should have been built or not. It is generally accepted that it was reasonable to make the decision to move the railway station to a museum as no one had cared about its heritage for decades.

"But the question is whether the Prime Minister or his office should be interfering in a planning matter several hundred miles from his constituency.

"The decision on whether or not to call in applications is non-political and should not be subject to political influence. It would be alarming if the Prime Minister or other Ministers were trying to interfere in the timing of decisions.

"If Wafic Said felt strongly about the proposal, he was entitled to say what he felt. But this sort of murkiness shows how right we are to be concerned how Labour and Conservative parties are over-reliant for funding on the wealth of a few very large businessmen who have their own agenda."

Shadow environment secretary Archie Norman said: "This appears to be another murky episode in which the Government has given preferential treatment to a project sponsored by their friends and close connections. We will be calling for a full investigation."

A Downing Street spokesman said: "This is a classic piece of newspaper innuedo, backed up by a few ridiculous quotes from a Liberal Democrat MP.

"The facts are that neither the Prime Minister nor any of his officials had anything to do with the decision."

Although the station was dilapidated and had been used as a tyre and exhaust garage, its removal was strongly resisted by 'green' campaigners.