A brutal battle to depose Iain Duncan Smith looks certain after the Conservatives' leader rejected a "final warning" from his own Chief Whip that he was losing the backing of his MPs.
On a day of frantic speculation at Westminster, David Maclean told Mr Duncan Smith that he had one last chance to bow out gracefully or face a vote of no confidence triggered by backbenchers.
The Conservative leader shrugged off the Chief Whip's advice and told the Shadow Cabinet he would fight on because he had earned the right to head the party into the next general election.
The grim message from MPs, which was passed on to the Tory party's whips, came after a former millionaire donor said that there was now an "overwhelming" case for a change of leader.
Stuart Wheeler, a spread betting tycoon who gave £5m to William Hague in the previous Parliament when he was leader, made clear he would not give any more cash until Mr Duncan Smith was removed.
Mr Duncan Smith was visibly frustrated today as his attempts to attack the Government's tuition fees and the system of drug testing in sport were overshadowed by speculation abouit his future.
Mr Duncan Smith was greeted with applause as he arrived in Loughborough, accompanied by his wife Betsy, to deliver a speech on Tory pledges to scrap the controversial charges.
But his continuing leadership crisis took centre stage and all talk of his policies was drowned out by questions from the media about calls for him to resign.
He hit back at opponents, saying: "This party will win the next election under my leadership. There is no question about my leadership. The question is, who is going to lead the country after the next election? And I can tell you now it is going to be me."
Some MPs predicted that the Leader of the Opposition now had between 48 hours and a week before 25 names would be gathered from MPs demanding a vote of no confidence.
Mr Duncan Smith is understood to have told colleagues that it would be "cowardice" to step down without 25 names being submitted to Sir Michael Spicer, the chairman of the Tories' backbench 1922 Committee.
But when asked what the leader would do once enough MPs came forward, one party source said: "That would be a very different matter."
Even his closest allies accept that Mr Duncan Smith could not survive a vote of no confidence. When Mr Maclean met the Tory leader yesterday, other senior party figures were understood to be present when the bad news was relayed.
In a desperate rearguard action last night, Conservative Central Office spokesmen stressed that any suggestion that Mr Maclean had told the leader that he had lost the confidence of the party was "complete fantasy".
But sources said that the Chief Whip, who is responsible for maintaining discipline among the party's MPs, had instead delivered the equally devastating message that support was slipping and that yesterday was the last chance to avoid a humiliating vote. At the 45-minute weekly meeting of the Shadow Cabinet, Mr Duncan Smith sought to clear the air over his future. Many of his MPs criticised what they saw as a lacklustre performance at Prime Minister's Questions.
The Tory leader took the unusual step of raising the issue under the "any other business" section of the shadow cabinet meeting. "I am aware that there are rumours today about a leadership challenge," he said. "I wish very simply to say to you that I am the leader of the party, I have the right to be the leader of the party and I intend to take this party through to the general election."
Despite rumours that one or more shadow cabinet members might resign to precipitate a leadership challenge, the meeting responded enthusiastically, with shadow ministers banging the table in approval.
Michael Howard, the shadow Chancellor who is also seen as a front-runner for leader, said Mr Duncan Smith deserved the party's support. "We have an elected leader of our party and he deserves our support," he told ITV News. "We should rally round him and offer him our support."
But opponents of the Tory leader are confident that they are "slowly but surely" gathering the 25 names needed under the party's rules to trigger a vote of confidence in Mr Duncan Smith. One frontbencher told colleagues yesterday that he would write to Sir Michael to ask for a vote - and said he knew of three others who would do so shortly.
Tory MPs were depressed by Mr Duncan Smith's performance in the Commons. "It was feeble," said one. "Iain's trouble is that every time he does something, he makes his position even worse." Another said: "It was the performance of a mediocre chairman of a provincial parish council."
The former party treasurer Lord Ashcroft admitted last night that big donors such as himself and Mr Wheeler were not keen to offer funds while the parliamentary party was disunited. "The money will flow into the Conservative Party once there is a unity of purpose. But why would anybody, including Stuart, myself and others support what appears at the moment to be a gaggle of squabbling losers," he told BBC Radio 4's PM programme.
Lord Ashcroft claimed that fewer than 20 MPs had either the "courage" or the constituency support to call for a vote of no confidence.
One senior ally of Mr Duncan Smith said: "They still don't have enough names and I don't think they will ever get them."Reuse content