Former Home Secretary David Blunkett has told Gordon Brown's allies to stop trying to make Tony Blair quit now.
Mr Brown has kept a low profile during the furore
He said: "It is now in Gordon Brown's - and the Labour party's - best interests for those seeking the prime minister's immediate departure to back off."
The plea came as Mr Blair faced a wave of resignations by junior members of his government over his refusal to name a date to resign as Labour leader.
On Thursday, he is expected to use some form of words to outline leaving plans.
It is thought his words will be along the lines suggested by friends that this will be his last party conference.
Earlier, Mr Blair branded ex-junior minister Tom Watson, the most senior person to quit, "disloyal, discourteous and wrong" for signing a letter urging him to go.
Mr Watson and the six parliamentary private secretaries (PPSs) - who are unpaid ministerial aides at the bottom rung of the government ladder - were among a number of normally loyal Labour MPs from the 2001 intake who signed a letter calling on Mr Blair to quit.
The six were: Khalid Mahmood, Wayne David, Ian Lucas, Mark Tami, Chris Mole and David Wright.
In a joint statement, four of the PPS group said Mr Blair had "not ended the uncertainty over when you intend to leave office, which is damaging the government and the party".
The resignations came as Mr Blair faces growing pressure to name a departure date or even quit now.
Gordon Brown's backers say assurances he will resign in May are "not enough".
But Mr Blair's supporters claim the calls for him to quit are an orchestrated plot by supporters of Mr Brown, who has so far declined to comment on the furore.
Mr Blunkett says the dissidents should "step back from the brink" and back off.
"This is not only to avoid our opponents exploiting the impression of disintegration and division, but also to avoid the split of our party, which would have lasting consequences," he said in a statement.
"No one can benefit from a split in the government or the party now, or in the foreseeable future, and this is patently avoidable by a return to common sense."
Mr Brown's allies deny he is plotting against Mr Blair.
But Labour backbencher John Grogan said: "We're looking to the chancellor I think now, Gordon Brown, to come forward and steady the ship."
"And if him and Tony Blair are not on the phone this afternoon then they should be and I think that's what most party members in the country think."
BBC political editor Nick Robinson said a close friend of Mr Blair and Mr Brown said the chemistry between them had now collapsed.
Also on Wednesday, it emerged that Environment Secretary David Miliband, seen as a potential deputy leadership contender, used an interview with The New Statesman magazine to make clear his support for the chancellor.
"The smooth transition to Gordon Brown, the energising, refreshing transition to Gordon Brown - not to anyone else - is a transition that is about ideas and values more than about dates," he says.