Gordon Brown has been accused of losing his way by Peter Mandelson, who attacked him yesterday for leaping on “passing bandwagons” while failing to tell voters what the Labour Party stood for.

As Mr Brown found himself assailed by criticism and gloomy polls, Mr Mandelson told him that Labour must get back to basics and rekindle its core convictions.

Such advice is likely to infuriate Mr Brown, who has long sought to project himself as the keeper of Labour’s conscience and assiduously courted the party’s union and grassroots power bases. It came as Lord Levy, formerly Labour’s chief fundraiser, sought to reopen tensions with Mr Brown’s predecessor in No 10 by claiming that Tony Blair told him several times that Mr Brown could never beat David Cameron in an election.

First extracts from the memoirs of Lord Levy, who was arrested in the police cash-for-honours inquiry but not charged, were published in The Mail on Sunday yesterday. Lord Levy said that Mr Blair told him that he thought his successor would be unable to match the Tory leader’s sense of timing, personality and natural ability to connect with voters in Middle England. He also revealed how he was asked by a senior figure within No 10 to confront Mr Blair over the “long massages” that the Prime Minister was reportedly receiving from Carole Caplin, the Blairs’ personal trainer.

Mr Blair swiftly issued a statement denying the claims about Mr Brown, but the row reinforced the impression of disunity within Labour. Lord Levy, who raised money for Labour for more than a decade, said he never doubted that Mr Brown knew of the secret loans from millionaires at the heart of the cash-for-honours saga.

He further said that, in Mr Blair’s final year at Downing Street when plotters attempted to force him to stand down, he railed at Mr Brown as duplicitous and branded him a liar.

Two polls added to Labour’s problems: an ICM/Sunday Telegraph survey gave the Tories a ten- point lead over Labour, and an ICM/News of the World poll of Labour-Tory marginal seats found a 9 per cent swing from Mr Brown to Mr Cameron.

Ministers tried to rally round Mr Brown, with several admitting in interviews that he faced a difficult period while blaming a midterm backlash and the global credit crunch.

The most candid intervention was from Mr Mandelson, a European commissioner, confidant to Mr Blair and, until recently, sworn enemy of Mr Brown, although in recent months he has offered the Prime Minister private advice.

“The party has got to pull itself together, refocus and make sure that it is presenting itself, what it stands for and its policies in a way that the public can understand and appreciate and feels is really relevant to their everyday concerns,” Mr Mandelson told Sky News.

“Looking to different passing bandwagons, or hobby horses or marginal issues really is not the way, in my view, for any government to present itself if it is going to sustain its support in the country. So I think that having been given a wake-up call, the party can and should refocus.”

His reference to hobby horses and marginal issues appeared to allude to Mr Brown’s attempts to follow the agenda of mid-market newspapers with such initiatives as banning plastic bags, holidays to celebrate the successes of the Armed Forces and his Britishness agenda.

David Miliband, the Foreign Secretary, led attempts to shore up Mr Brown’s position, but said that Labour must “make sure that people can see, in what we do, the convictions that hold us together as a party”.

The message that Mr Brown must make clear what Labour stands for was reinforced bluntly by Graham Stringer, a disaffected Labour MP, who said that people in his Manchester Blackley constituency did not understand the compensation pledged for those who lost out from abolishing the 10p tax rate.

“What the Labour Party needs to do is start communicating its central message as clearly as possible, which is to be on the side of the poor and the weak, and the whole of the 10p fiasco and the 42 days [anti-terror] proposals actually make that very unclear as to whose side we are on,” he told The World This Weekend on BBC Radio 4.

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