Deputy prime minister John Prescott dismissed reports of a possible leadership contest against Tony Blair.

Speaking on the BBC Radio four Today programme, he did concede that concerns existed among Labour backbenchers regarding possible military action in Iraq and the use of the private sector in delivering public services.

"I'll give you my judgement - I think this government is doing a good job. Nobody is suggesting that Tony Blair would be changed as leader. If they did, there is a process for that. Nobody is going to exercise that," he said on Wednesday.

"We have got to recognise that in this stage of government of its second term, we may have some difficulties and exchanges but we have to work at that."

His comments followed a meeting of the party's national executive committee, at which Blair urged more leftwing MPs to trust him on public service reform.

"Of course there is concern - I don't want to dismiss that. They come up to me and they talk about some of these things and we have got to work at it. But Tony Blair is a guy, let's face it, who does get into the debate whatever is said about that," said Prescott.

"What some mean is that he doesn't change his mind on his position, like they don't change their mind on their's."

However, Hayes and Harlington MP and leader of the Socialist Campaign group, John McDonnell, warned that Labour could lose the next election on issues like Iraq and public services.

"On peace, we as a party always had a preference to peace rather than a leap to war - that has not been displayed on Iraq," he said.

"As a party we have always supported public services, not privatisation. What won us the election was the rejection of Tory policies - some of which this government is now taking up, like privatisation - and they will lose the election in the same way they lost the Tories the election, if we are not very, very careful.

"I think I want Tony Blair to allow a debate to happen on these key policy issues - whether he comes or goes is up to him," he added.

However, Prescott claimed that McDonnell had a track record of being a rebel.

"John McDonnell when he was a councillor he split with the London council; when he was in Ken Livingstone's cabinet, he split with them; when he is in the Parliamentary Labour party, he splits with them," he said.

"Don't let's talk as if all of a sudden he has come from a unity base and now he is being concerned."

The interview came as former culture secretary Chris Smith wrote in the Evening Standard that the government had to listen to criticisms over a wide range of policy areas, including transport, crime and the Post Office.

"Most of these issues land up in some shape or form in the government's lap," he wrote.

"They have to be dealt with and sometimes there are simply no easy answers. That is part of the inevitable process of government and ministers have to develop thick skins to survive.

"There is genuine concern among many parliamentary colleagues about the possibility that we might get pulled into an invasion of Iraq without broad international consent. I share that concern," he said.

However, he too dismissed claims of a "stalking horse" existing to challenge Blair.

"A handful of mavericks - probably even less than a handful - may have been muttering away in the Commons tea room, but that is the sum of the total alleged 'rebellion'," he wrote.