Whip claims in contest for Speaker

Leader of the Commons Harriet Harman denied a behind-the-scenes operation was being staged to make the former Foreign Secretary the third Labour Speaker in succession.

But one Labour backbencher called on whips to stop "touting" the Derby South MP, who has emerged as the 11th-hour favourite, as support for Conservative John Bercow apparently ebbed away.

Candidates to succeed Michael Martin in the famous green leather chair were required to register their nominations with the Commons authorities and had to be backed by the signatures of between 12 and 15 fellow MPs, at least three of whom must come from outside their own party.

At the close of nominations, there were a total of 10 candidates in the race - Labour's Margaret Beckett (Lab) and Parmjit Dhanda, Lib Dem Sir Alan Beith (Lib Dem) and Conservatives John Bercow, Sir Patrick Cormack, Sir Alan Haselhurst, Sir Michael Lord, Richard Shepherd, Ann Widdecombe and Sir George Young.

The new Speaker will be chosen for the first time by secret ballot, with MPs taking part in a series of rounds of voting which will take up the whole of Commons business for Monday.

In each round, the candidate with the lowest level of support will be eliminated, along with any receiving less than 5% of the vote.

The winner is the first to secure more than 50% of votes cast in any round. Whoever wins will be charged with restoring trust and confidence in Parliament in the wake of its battering over the expenses scandal.

The election will take place against the backdrop of criminal inquiries by the Metropolitan Police into a number of MPs' expenses claims.

Mr Martin, Speaker since 2000, officially vacated the position on Sunday after being forced out by MPs angry at his handling of the crisis.