Michael Portillo deepened Iain Duncan Smith's leadership crisis last night with a challenge to him to prove he is up to the job.
The former defence secretary, who unsuccessfully stood for the leadership last year, became the first senior Tory to admit publicly that there was disquiet on the party benches over Mr Duncan Smith's performance.
Mr Portillo told Five News: "I don't want to kid you there have been mutterings.
"Iain Duncan Smith has to fight back. I think the position is perfectly retrievable, but he has got to fight for it, he has to show he wants the leadership, he has got to show which direction he is leading us in."
But Mr Portillo could not categorically state that Mr Duncan Smith would be leader by the next election. "I can't tell what's going to happen, but I'd say that if Iain wants to pull the situation back, he can."
His intervention came as it emerged that Mr Duncan Smith could face moves to oust him as Tory leader before next May's elections to local authorities, the Scottish Parliament and Welsh Assembly. He has previously been regarded as safe until then.
In a further ominous development for Mr Duncan Smith last night, a senior frontbencher said that the Tory leader's response to the Queen's Speech on 13 November would be "a key test" for his survival.
Mr Portillo said the Tories would make fools of themselves by deposing a leader at this stage, but called on Mr Duncan Smith to "make some very strong speech or very strong statement" to prove he had a grip on the party. Mr Portillo, who denied that he still harboured ambitions of becoming leader, said Mr Duncan Smith's position was "difficult but not desperate" and that he needed to be "sufficiently proactive" to recover.
But William Hague, the former Tory leader, today seeks to lower the feverish manoeuvring among MPs with a warning to the party that it cannot hope to regain power if it keeps ditching its leader. "I know of no possible leader of the Conservative Party who would not have to face the same issues and inevitable difficulties. I hope the rumours I read of plots against my successor are soon forgotten," he writes in a newspaper article.
He also argues that the leadership's strategy of focusing on the Government's handling of the public services could pay dividends.
At the Tories' annual conference in Bournemouth this month, Mr Duncan Smith appeared to have won a stay of execution until next May. But morale among Tory MPs has slumped after the conference failed to boost the party's opinion poll ratings and amid criticism of the leader's lacklustre performances in the Commons.
Yesterday one Tory frontbencher said the party leader was only "one gaffe away" from provoking an immediate challenge to his leadership. He said Mr Duncan Smith's "staggeringly inept" performances in recent weeks had undermined confidence in him, in the Shadow Cabinet and the rest of the party.
Twenty-five Tory MPs need to demand a vote of confidence in the leader to trigger a contest. Some senior Tories now believe there is a "50-50 chance" of this happening. One said: "People say that we need to wait until after the local elections, but that's a distraction. With modern polling methods, we don't need to wait until the May elections to know how badly we are doing."
Kenneth Clarke, who was defeated in the final round of last year's leadership contest, has told fellow MPs it is "incontrovertible" that the party leader has performed "badly" in recent weeks. Meanwhile a Tory frontbencher revealed that Mr Portillo's allies had been "active" this week for the first time since he was defeated last year.
Several MPs have complained that Mr Duncan Smith has been virtually invisible at Westminster, saying his recent nationwide tour has been a waste of time. His aides insist the tour has raised his profile in the country, and dismiss the criticism as coming from "the Westminster village".
The Tory leader fought back at Prime Minister's Questions yesterday when he put Tony Blair on the defensive over whether he would allow universities to charge top-up fees and on waiting times for patients at hospital accident and emergency departments. He won loud cheers from Tory backbenchers, although some critics said later the party's whips had mobilised loyalist MPs for a show of support.
Baroness Thatcher told Mr Duncan Smith yesterday that he must be a "conviction" leader to survive.
"Convictions drawn from outside politics are also required to take the right political decisions," she said. "Our beliefs must anchor us firmly, if we are not to capsize in the daily storms of office."
Last night allies of Mr Duncan Smith acknowledged there was unrest among some MPs, but insisted it was limited to a small group which had never accepted his victory last year over Mr Clarke. They said they expected rocky spells during his leadership, but that he continued to focus on reshaping the party's strategy and public image.
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