A former Labour MP this week launched a scathing attack on Lord Levy for publishing memoirs which reveal inside details of Tony Blair’s government. Many of Lord Levy’s targets appear to be Jewish, from Carole Caplin to Sir Ronald Cohen.

Eric Moonman, an executive member of the Association of Former Members of Parliament, hit out at the former chief Labour fundraiser and Middle East envoy for spilling the beans.

Extracts from A Question of Honour, due to be published on May 18, appeared in The Mail on Sunday at the weekend and included the claim that while Prime Minister, Mr Blair had told Lord Levy that Gordon Brown could never defeat Tory leader David Cameron in his election.

Mr Moonman told the JC: “What we know of the manuscript is nauseating and disagreeable. It is tantamount to a breach of private conversations and confidentiality with ministers.

“It could well prejudice any future role for Jews working for or advising those in government.”

In light of Labour’s current poll rating being well behind the Tories’, he added: “These revelations could hardly come at a worse time. Labour is on the back foot. The Labour leadership will not forgive or forget what has been said.”

Lawrie Nerva, a former local councillor and now treasurer of the Jewish Labour Movement, said that he was “appalled” that Lord Levy should have chosen the Sunday before this week’s local and London mayoral elections to publish extracts that “could prove damaging to Labour”.

He said: “Levy’s revelation that Tony Blair believed Gordon Brown ‘could never beat’ David Cameron in a general election reveals a lack of respect for both Blair and Brown and a total disregard of the damage to Labour’s standing at a time when all Labour supporters should be seen to be closing ranks.”

Labour MP Louise Ellman would not join the criticism, however, saying she had “no knowledge of the validity” of any of the statements in the book, but observing that “the more provocative they are, the more readers they get”.

The published extracts tell of Lord Levy’s ordeal under the cash-for-honours investigation and his relief when told that no prosecution would be brought. They also go into his relationship with Tony Blair, a frequent visitor to the tennis court and swimming pool at the peer’s North London home, and the Prime Minister’s difficult relations with his Chancellor Gordon Brown.

He reveals that when Mr Blair asked him to patch up relations between Mr Brown and another key party figure, Peter Mandelson, Mr Brown exclaimed: “Peter? He’s been going around telling everyone that I’m gay.”

Lord Levy admits that he was “upset and angry with Tony” when learning that in the run-up to the 2005 election the Prime Minister had turned to venture capitalist Sir Ronald Cohen for help fundraising “behind my back”.

He also says that the Prime Minister “went red” when he warned that Cherie Blair’s friend, Carole Caplin, the lifestyle coach, could “become an issue… for you”.