Lord Levy voices concern over Gordon Brown's leadership
Lord Levy, who was at the centre of cash-for-honours allegations, has criticised the "lack of strong leadership" in the Labour Party.
And the man who was ex-PM Tony Blair's chief fundraiser said he was saddened by the "bickering" within the party.
He also claims Mr Blair had told him Gordon Brown could not beat Tory leader David Cameron in an election - which a spokesman for Mr Blair has denied.
His comments came in an interview for The Mail on Sunday.
The interview coincides with the serialisation of his memoirs in the newspaper.
In his book, Lord Levy writes that Mr Blair "told me on several occasions he was convinced Gordon 'could never beat Cameron'".
The newspaper quotes the peer as saying Mr Blair claimed he was convinced he could win a fourth term if he stayed on at Number 10.
"But Gordon? 'He can't defeat Cameron,' Tony told me," Lord Levy writes.
"Blair believed Cameron had major strengths - political timing, a winning personality and a natural ability to communicate to Middle England that Gordon would be unable ever to match."
A spokesman for Tony Blair said: "Tony Blair said when he stood down that he would be 100% loyal to Gordon Brown and that continues to be the case.
"He doesn't agree with the views attributed to him by Lord Levy and fully believes Labour with Gordon Brown's leadership can win the next election."
'Total belief' in Blair
Explaining his comments in an interview with the newspaper, Lord Levy said: "Firstly I'm a Labour man, always will be a Labour man, always have been a Labour man.
"My parents were, my family are, and I will never change my political viewpoint.
"I absolutely had total belief in Tony Blair, and I felt it was a privilege to help in any way I could both he and the Labour party.
"I really am saddened to see the polls at the moment, what's happening with the party, the bickering within the party, and frankly what I and many others now perceive as a lack of strong leadership."
During the interview, Lord Levy also talks in general terms about the cash for peerages inquiry, and suggests he was opposed to the idea of the party accepting loans.
He also suggests in the book that Gordon Brown knew Labour had accepted loans to help fund its 2005 general election campaign.
But a Downing Street source said it had always been made "categorically clear" without "any equivocation" that Mr Brown knew nothing about the loans.
In the "cash for honours" row, Labour was secretly lent £14m ahead of the 2005 election. It subsequently emerged that some of those lending the money had been nominated for peerages. The party, and the businessmen involved, denied any wrongdoing.
Scotland Yard investigated complaints that Labour and other political parties had broken laws dating back to 1925 about selling honours, and several people were arrested - including Lord Levy - but no-one was charged.
Lord Levy has since called for a change in the way political parties are funded, calling for a cap on donations and more state funding.
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