Rebel Labour MPs were last night accused of staging a coup to oust Tony Blair.
Backbenchers say uncertainty about the Prime Minister's future is damaging the Government and they want him to set a date for his departure.
But Blair loyalists have accused them of trying to force him out of office. And they have warned they are playing a "very dangerous game".
Mr Blair has made clear he will stand down before the next election. He has said he will serve a full third term, but repeatedly refused to say exactly what that means.
But backbenchers say he must now make clear when he plans to go. A draft letter, thought to have the support of around 50 MPs, says Mr Blair should be given until summer to lay out a clear timetable for the handover of power.
Arch-Blairite Stephen Byers condemned the plot. The former Transport Secretary said: "If we want to have an orderly transition, what we cannot have is the forced removal of Tony Blair as our leader.
"And for those people who are organising a coup against him, they are playing a very dangerous game and they should stop."
His message was under-lined by new Home Secretary John Reid. He warned the plotters: "They are not going to win."
He said: "The whole thing has been generated by people who want to push Blair out. Those people who are trying to shove Blair out, change the direction, use the situation to put us back to Old Labour - they are not going to win."
And Labour press chief David Hill said those demanding a timetable really wanted to "get rid of the Prime Minister very quickly and move away from New Labour".
Mr Hill made the comments in a text message to a journalist. It had been suggested the message was sent to MPs, but Mr Hill insisted it had not.
However, the attacks have sparked outrage among Brownites. Mr Brown's key ally, former minister Andrew Smith, said: "I am furious and the party will be furious about attempts to stifle or stop the discussion which needs to be had about a timetable for the orderly transition of leader-ship which is what we need and what party members want so that we can get the renewal of the Labour Party. This is an important and legitimate debate that has to be had about the timetable for an orderly transition following the message which I and others will have got from voters in the campaign on the doorstep."
The Chancellor himself underlined his demands for a stable and orderly tansition.
But he said "we don't need outriders dictating the agenda" as everyone wanted an orderly handover.
He refused to endorse back-bench calls for Mr Blair to name the day for his departure.
But he said people would be looking to the Prime Minister to organise the transition.
Mr Brown said the vast majority of people in the Labour Party and the wider country wanted a "stable and orderly" handover.
"Because we are in a unique situation where the leader has said he is not going to stay on, then that stable and orderly transition which Tony Blair has said that he wishes to manage - I think people will look to him."
He added: "I think people will look to him, and it's not essentially a matter for me, it's a matter for him and the Labour Party."
Mr Brown made it clear it was his task to help develop the policies and party organisation for the future.
He said in "the next stage of my political career" he would ensure Labour broadened its support base.
He said he did not know when Mr Blair would quit.
"It is a matter for Tony and the Labour Party themselves and no doubt people will continue to discuss this with him. But at the end of the day I get on with my job."
The letter circulating among MPs says Labour's record is being overshadowed by "debilitating" speculation over Mr Blair's future. They want to see a "dignified, orderly and efficient" transition of power.
The letter says a prerequisite for that is "a clear timetable and transparent procedures".
It adds: "We therefore ask the NEC, in consultation with the Prime Minister, to lay out, no later than the end of the current Parliamentary session, a clear timetable and procedure for the election of a new Labour Party leader." ..SUPL: