As counter-attack tactics go it wasn't the best, and he could certainly have picked an easier target. But Edward Leigh, the Conservative MP for Gainsborough and Market Rasen, was sure he could redirect taxpayers' fury away from politicians and onto the shoulders of ... John Humphrys.

He failed miserably, but the chairman of the House of Commons Public Accounts Committee (PAC), which today published a report on the huge, secret salaries paid to BBC radio presenters, did at least cause Humphrys to squirm on BBC Radio 4’s Today programme.

Mr Leigh, said it was disgraceful that the BBC had refused to publish the salaries of its presenters, so he wanted to know exactly how much of the licence fee Humphrys takes home every year.

“We, the public who pay your salaries, John, should have an idea of what you earn. I mean, you do a very good job but for instance: do you earn more than the Prime Minister, John?” he asked on Today.

“Well, I’d love to be able to tell you that,” Humprys replied.

“Why don’t you?” asked Mr Leigh. “It’s a free country.”

“Well. . . well,” the caustic presenter stuttered. “As far as most presenters are concerned, and I include myself in that, we're not going to break ranks because it's for the BBC to make this decision. We're freelances."

Humphrys refused to follow the example of BBC news presenter Carrie Gracie who admitted to Lord Foulkes, during a live television discussion of MP’s expenses, that she was paid £92,000.

Mr Leigh suggested that if the public knew how much Humphrys was paid, they might be able to find someone “younger” who could do the job more cheaply.

"I think that is an appalling state of affairs for a publicly funded body,” Mr Leigh said. "It is disgraceful that the National Audit Office's lack of statutory audit access to the BBC puts the corporation in the position to dictate what the spending watchdog can and cannot see.

"All of this places a big question mark over whether the BBC is achieving value for money for the licence payer."

The BBC Trust commissioned the National Audit Office (NAO) to review the efficiency of the BBC's radio stations. The auditor asked for details of the staff and presenters salaries, but unlike other publicly funded bodies, the auditor does not have legal unrestricted rights of access to the BBC's accounts.

The BBC refused to hand over a breakdown of salaries for a selection of radio shows unless the NAO signed a non-disclosure agreement.

A committee of MPs said this morning that it had therefore been unable to make a complete and independent assessment of the BBC's costs. However, the PAC said it had seen enough to suggest that the BBC appeared to be paying some of its radio presenters more than twice what commercial stations pay theirs.

The report found that programmes such as Sir Terry Wogan’s Wake Up to Wogan on Radio 2 cost on average twice as much per hour as the most expensive commercial breakfast show.

For the corporation’s breakfast and “drivetime” shows, presenters’ salaries accounted for around three quarters of the total staff costs.

The MPs said the BBC’s main value for money test, the so-called “cost per listener hour”, which takes the size of audience into account, risked creating an inflationary wage spiral, and should be balanced with a range of other measures.

The BBC Trust, the corporation’s governing body, said it was “disappointed” the NAO would not sign the non-disclosure agreement.

Jeremy Peat, a BBC Trustee, said: “The Trust is committed to ensuring value for money for licence fee-payers. That’s why we have commissioned a series of such studies from the NAO and others.

“We have always previously supplied the NAO with the information they request and it is in our interests to do so, in order to ensure studies with robust conclusions.

“We were therefore disappointed that - in contrast to other auditing organisations we work with - on this occasion the NAO wouldn’t sign an agreement to ensure that the BBC did not breach its legal obligations to staff."

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