Michael Heseltine's calls for Conservative MPs to ditch their leader have been branded "irrelevant" by Iain Duncan Smith.

Former Deputy Prime Minister Lord Heseltine says Tory MPs should defy the party's grassroots members and choose someone else to lead them in Parliament.

Michael Heseltine is a serial Conservative assasin

Lord Tebbit

Otherwise, he warns in a newspaper interview, the party will not have "a ghost of a chance of winning at the next election".

Other senior Conservatives have branded Lord Heseltine's idea "absurd" and Tory officials branded the comments a "ridiculous fantasy".

Mr Duncan Smith said: "It is one of the most irrelevant stories I have ever heard."

Clarke's potential

A Tory spokesman said Lord Heseltine had said similar things when William Hague was leader.

"We regard this as nothing new at all," the spokesman added.

John Strafford, chairman of the Campaign for Conservative Democracy, said many people in the party hierarchy were actively planning how to anoint Ken Clarke as leader, with Michael Portillo as his deputy.

Iain Duncan Smith warned his party to "unite or die"

Former chancellor Mr Clarke's pro-European views are seen as a major obstacle to him being elected by the party's grassroots.

Mr Strafford suggested MPs could circumvent that problem by agreeing on only one leadership candidate - although Mr Duncan Smith would need to resign first.

Despite the government's problems, the Tories were failing to go on the attack, argued Mr Strafford.

But he also accused Lord Heseltine of treating party members with arrogance and contempt.

Clarke's potential

In his interview, Lord Heseltine says: "We've got a better shadow cabinet on the back benches than we have in the actual shadow cabinet on the front bench."

Last month Mr Duncan Smith issued a stern warning to Tory rebels that they should unite behind him if the party was to be taken seriously.

His message came little more than a year after he had won a leadership ballot of the 350,000 party members.

Norman Fowler says it would be absurd to change leader again

But on Monday Mr Heseltine urges MPs to ignore the party membership and look to Mr Clarke as a potential replacement.

Lord Heseltine acknowledges that under the current leadership rules, which give the final say on who should be leader to the membership, it would be impossible to install pro-European Mr Clarke in the top job.

Extreme wing

He said: "The parliamentary party should say, 'Those are the rules of the party as a whole, but we are going to have a separate leader for the parliamentary party'.

"They would then choose Ken Clarke. I suspect also that this would bring Michael Portillo back into the front line."

It would be a "constitutional aberration", but was aimed at helping the party recover.

Lord Heseltine, a keen Europhile, was dismissive of the party membership, suggesting that MPs would have selected Mr Clarke as William Hague's successor had it not been for the final choice going to the Eurosceptic activists.

'Absurd' idea

"You are dealing with a small number of people - the party members - with an average age of 67, who are obsessed with this issue of Europe," says Lord Heseltine.

"The members of the Conservative Party are repeating in a worrying way what happened to the Labour Party in the early 1980s.

"They have closed in on themselves and withdrawn to the more extreme wing of the party."

Such comments are bound to anger many grassroots members, particularly those who voted for Mr Duncan Smith.

Former Conservative chairman Norman Fowler said it would be absurd for the party to turn its back on its activists.

Lord Fowler said: "About the last thing we frankly need is a division between the parliamentary party on one side and the party in the country on the other."

Another former Tory chairman Lord Tebbit was even more forthright, calling Lord Heseltine a "serial Conservative assasin".

"His fear is not that Iain Duncan Smith might lose the next election," said Lord Tebbit.

"His fear is that Iain Duncan Smith might win the election and lead a Eurosceptic government that would refuse to submerge Britain into in the proposed European republic."