An emergency resolution will be sent to all constituency Labour parties calling for Blair to quit because of his "disgraceful" policy in Iraq, and for a leadership election within two months of the conference.

Blair will seek to shrug off the challenge, but it has been tabled by leaders of the Campaign for Labour Party Democracy, who successfully backed four candidates elected to the National Executive of the party, including the veteran anti-war campaigner Walter Wolfgang.

The calls for Blair to go will be boosted by the burst of support for John Prescott that has occurred since newspapers disclosed his comments that Bush's performance on the Middle East road-map was "crap".

Prescott is worried the remark may damage him, but there has been support for his words about Bush to a private meeting of MPs. "I think he could get a standing ovation now, " said one of his close friends.

"He's said what a lot of us have been thinking."

The call for a new leader is also intended as a spur to Gordon Brown to force Blair out.

"So far, Gordon has been too afraid to strike. He has got to demonstrate that he is ready for the leadership by helping the party to get rid of Blair, " said one NEC member.

The group want Prescott to stay on as deputy to let Brown secure the leadership, before a contest for the deputy's position. "Alan Johnson [the education secretary] is Blairite. He won't win the deputy job. Peter Hain [the Northern Ireland and Wales secretary] could do better. Reid [the home secretary] could throw his hat in. He has got a lot going for him at the moment, but we don't want some Blairite getting the deputy leadership. We want the Blairites totally destroyed, utterly obliterated, " he added.

Tony Blair will have served as leader for 10 years next May, but a motion tabled at the Labour conference in Manchester seeks to prevent any leader and deputy from serving more than 10 years.

Others are calling for the the practice of sending nomination forms to MPs for the leadership on an annual basis to be reinstated, in order to to reinforce the threat to ditch a future leader who becomes out of step with the party.

The conference may also trigger a row over the official Labour submission to the inquiry into party funding. Most members oppose state funding of the parties, but support restrictions on general election spending.

The leadership is expected to come out against state funding, but there could be protests over suspicions that the Blairites want to use the review to break the party's historic link with the trade unions.