Senior MPs are canvassing four potential successors, amid signs of growing pressure on Michael Martin to stand down soon as Speaker of the Commons.

Even before Mr Martin became embroiled in the row over MPs’ expenses and his own conduct was called into question by reports about his alleged use of officially accrued Air Miles for his family, leading backbenchers were privately suggesting that he should go this year so that the present Parliament could elect his successor.

They are arguing that, if Mr Martin waits until the end of this Parliament in 2009 or 2010, the new Parliament could contain many new MPs who would not be familiar with the candidates putting themselves forward for the most important post in the Commons.

Sir George Young, chairman of the Commons Standards and Privileges Committee, Sir Alan Haselhurst, a Deputy Speaker from the Conservative side, Sylvia Heal, a Deputy Speaker from the Labour side, and Alan Beith, the veteran Liberal Democrat MP, have emerged as the leading figures to take over from Mr Martin.

When the election comes it will be the first to be held by secret ballot, after MPs decided that it was invidious for Speakers to know how they had voted.

There will be no overt attempt to remove Mr Martin. Most MPs agree that if he wants to stay on until the next election they cannot stop him. The only real mechanism for ousting the Speaker, who took over in 2000, is pressure. One Speaker in the last century whose fondness for alcohol eventually caused him embarrassing moments in the chair finally left the post when the “usual channels” - the senior figures responsible for Commons business on both sides – told him that his time was up.

What is worrying well-placed MPs – including members of the Labour and Conservative front benches spoken to by The Times yesterday – is that he has as yet given no indication that he would be ready to go even then. One Tory frontbencher said: “He needs to let it be known pretty quickly that he sees no future for himself in the next Parliament. Otherwise the usual channels may have to do their worst yet again.”

A Labour ex-minister told The Times that Mr Martin would “do himself a favour” if he let it be known that he would bow out in good time for the next election. “People are not happy with him. They don’t want to see the office of Speaker damaged. He has had a good run, eight years, which is effectively two Parliaments. If he says he will be going soon, his short-term problems will be over.”

Sir George stood in the last election for Speaker. He is popular on all sides of the House. It was his committee that delivered the verdict on Derek Conway about the employment of his son that led to withdrawal of the Conservative whip. Sir George has irritated the Speaker by carrying out a speedy inquiry into the reform of MPs’ expenses whereas he has proposed a more leisurely approach.

Sir Alan, a youthful 70, is also well liked among MPs of all parties and several Labour MPs have said that they would be prepared to support him. Mrs Heal is the most obvious Labour candidate and has been a Deputy Speaker since 2000. The narrowness of her majority in her Midlands seat is seen as a disadvantage by some. Labour MPs might be happy to support the claims of Mr Beith, a former Liberal Party Chief Whip, in the absence of other candidates.

The next Speaker would by tradition be a Conservative because the last two have been Labour, but there is no hard-and-fast rule and many Labour MPs believe that they should use their party’s majority in the Commons to opt for another Labour Speaker. But with the ballot secret, the less tribal Labour MPs may well go for a candidate from another party.

The Commons decided in 2001 to make the next election confidential after the contest that elected Mr Martin involved eleven candidates and seven hours of voting. MPs prefer the Speaker not to know how they voted because they rely on him to call them to speak in debates and fear that he or she might have a long memory.

Hopefuls

Sir George Young, 66, thoroughbred praised for chairmanship of Standards and Privileges Committee. The “bicycling baronet”
Sir Alan Haselhurst, 70, stayer who has impressed all sides as a calm, firm and unexcitable Deputy Speaker
Sylvia Heal, 65, outsider because of narrow majority. Competent, unflamboyant Deputy Speaker
Alan Beith, 64, shrewd, sensible, slightly dour. Might cause a surprise if Labour MPs back him

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