After a weekend of continued in-fighting, the Conservative chief whip, David Maclean, has today accused Michael Portillo of "selfish and destructive" behaviour.

Writing in today's Telegraph, Maclean admits that critics of Iain Duncan Smith have been plotting his demise.

"What a crazy time to raise the spectre of a leadership challenge. I know that over the past few months colleagues have been looking at all possible names and coming up with some fantastical scenarios.

"But I can tell them there is no messiah waiting in the wings who will command more support than Iain."

Members of the shadow cabinet were despatched to broadcasting studios yesterday to defend their leader.

Tim Yeo, the party's culture spokesman, said that with the country possibly two or three weeks away from going to war, the public would think the Tories "had gone off our heads" if they embarked on a leadership battle.

Francis Maude, a former shadow foreign secretary, told Radio 4's The World This Weekend: "The party needs to lie down in a darkened room for a period and gather itself together."

However, John Bercow, who resigned from the shadow cabinet over Duncan Smith's opposition to gay adoption, said a leadership challenge could be imminent."I think it could happen sooner rather than later," he told BBC TV's Breakfast with Frost. "There is clearly grave disquiet."

Although the FT says that senior party officers are already discussing the arrangements for an election, today's Times says that MPs will wait to see the results of May's local elections before mounting a leadership challenge.

Today's Sun quotes one Tory backbencher who claims that Duncan Smith is a "dead man walking".