Former Conservative prime minister Lady Thatcher is refusing to be drawn into the simmering debate in the party about a possible challenge to William Hague's leadership after the general election.

A little school marmish talk of the need for iron discipline would raise spirits

Gerald Howarth

A call for her to intervene to help boost Mr Hague's authority has been made by the backbench MP Gerald Howarth, amid reports that shadow chancellor Michael Portillo will be put forward as a rival with the help of former chancellor Kenneth Clarke.

Mr Howarth - a former parliamentary aide to Lady Thatcher - told the Daily Telegraph newspaper: "I think it would help enormously if Margaret said something. She still commands huge respect and affection, and remains a commanding figure."

But a spokesman at her office said she did not wish to become involved.

Iron discipline

Lady Thatcher publicly backed Mr Hague for the party leadership in 1997, and Mr Howarth believes another ringing endorsement might well be welcomed at Conservative Central Office.

"She is the grandmother of the Tory Party. A rallying call, a little school marmish talk of the need for iron discipline, would definitely raise the spirits," he said.

Gerald Howarth worked for Lady Thatcher

Lady Thatcher's spokesman said: "I have spoken to her and she does not want to get involved."

Party chairman Michael Ancram also refused to be drawn into the apparent in-fighting over the leadership.

He told BBC News: "What I would say on behalf of the shadow cabinet is that we are all single-minded in our determination to achieve victory at the general election."

Asked whether Mr Portillo and Mr Clarke should make statements on the matter, the Tory chairman said: "Mr Portillo has made his position clear in the past.

"I don't think it is very wise that every time a newspaper speculates it drives politicians into repeating things they have said previously.

"Ken Clarke ... did come out and make it quite clear that he denies that speculation."

Neutral candidate

But the debate has been further fuelled by a leading contender to take over as chairman of the influential 1922 Committee of backbench Tory MPs, a post which will fall vacant after the election.

Gillian Shephard - a cabinet minister under John Major - launched her campaign for the job on Tuesday by declaring that she would be the "neutral candidate" who could be relied upon to manage any leadership challenge fairly.

She told the Times newspaper: "There could be a feeling that we need a change, but it could be the opposite.

"It depends on what sort of campaign William has, and I think he will have a very good one."