Voters were watching aghast as Labour tore itself apart, Jon Cruddas said last night in rebuke to the Blairites who are driving efforts to topple Gordon Brown.

In an interview with The Times, Mr Cruddas said that none of those who claim to be Tony Blair’s allies come close to matching the former leader.

The Dagenham MP, who is one of David Miliband’s rivals to succeed Mr Brown, turned down a ministerial job last summer despite being most members’ first choice as deputy leader. He suggested to The Times that he was now willing to take a job under Mr Brown.

The Prime Minister is also preparing to confront his critics, and will tell them today that “this is not a time for faint hearts” while warning his Cabinet to show more discipline. Leading Blairite members of the Cabinet, including James Purnell and John Hutton, have refused to condemn the MPs who have called for a debate about Mr Brown’s leadership.

Mr Cruddas said that MPs had been reckless, irresponsible and divisive in calling for change without a candidate, timetable or alternative policy programme. “People will be watching with wide-open eyes unable to understand that . . . we should become preoccupied with electing another party leader. That’s what’s so wrong,” he said.

Although he admitted that Mr Brown’s electoral prospects “don’t look good”, he said that a leadership election could leave the party in a worse position by entrenching divisions. The rebels were “poisoning the well” and making it harder for the party to unite either under Mr Brown or a new leader, he said.

A poll of Labour activists by Labourhome.org found that the majority want a new leader. Mr Miliband, the Foreign Secretary, was the favoured candidate, with 24.6 per cent, and Alan Johnson, the Health Secretary, was second, with 18.1 per cent. Mr Cruddas was backed by 11.3 per cent of those polled.

Mr Cruddas, who worked in No 10 under Mr Blair, sought to wrong-foot those who would dismiss him as a leftwinger, praising Mr Blair’s “genius” and making a barely coded attack on those such as Mr Miliband who were “acting under his banner”.

“Blair was a much more charismatic, sophisticated, inclusive and radical politician than any of those who claim adherence to Blairism now,” he said.

Mr Cruddas signalled that he was willing to shore up Mr Brown’s battered administration. “It’s all hands to the pump now,” he said. “A year ago I said my [deputy leadership] campaign wasn’t about a job in government and I felt you had to carry that through. My instinct is not oppositional. Whoever is leader, we’ve got to think how we put the band back together.”

He praised both Mr Miliband’s and Mr Purnell’s efforts in taking on the Conservatives. Labour had not laid a glove on the Tories for more than a year, he said. He criticised attempts to portray David Cameron as a “shallow salesman” and as a right-wing Tory posing as a moderniser. Instead, he urged his party to match Mr Cameron’s emotional literacy and expose the tensions between the Tory party’s liberal and authoritarian wings.

Mr Cameron, he said, would struggle to maintain his compassionate credentials during an economic downturn.

Mr Brown’s failure to rally his party was exposed during Tuesday’s Cabinet meeting when Hazel Blears, the Communities Secretary, demanded to know why ministers were not being shown polling data on Labour’s own unpopularity. However, in an interview aired today, Mr Brown makes plain that he has no intention of going before the next general election.

“I believe all of the energies of the whole of the Government and all of the party should be used getting the country through these difficult times,” he tells Sky News.

“People who know me know I feel very concerned about the tragedies and difficulties faced in our country. Why did I come into politics? I could have done anything else. I felt public service could make a difference to our country. If it turns out that that is not the case, then that is for the people to judge. I am trying to do my best for the country.”

Asked why he is not holding a leadership contest, he replies: “I have been in politics a long time. You go through periods. Sometimes you are popular, sometimes people resent the decisions you make and sometimes people are disappointed.

“You always get that. You take the rough with the smooth. You deal with the problems you face.

“The proof of being a good government is getting on with taking people through these difficult times and planning for the future.”

He says that the Cabinet has a duty to work together for the country. “Every Cabinet takes a few months to settle down. We are a team. We are working together we have a common purpose.

“We would fail the country if we did not discharge that purpose as a group of people working together and doing so in a very disciplined way and that is what I intend to continue doing.”

Mr Brown also explains why he will not expose his children, Fraser and John, to the media. “I made a choice to go into politics. Sarah married me and knew I was a politician. She made that choice and we work with each other doing the things we do. But our children did not make that choice. I have to protect young children growing up who I want to have an ordinary childhood.”

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