by political editor Paul Francis

Ashford MP Damian Green says the House of Commons must have a powerful and respected Speaker to oversee urgently-needed reforms to restore Parliament’s credibility.

As a member of the shadow cabinet, the Conservative MP declined to say whether he wanted the current Speaker Michael Martin to stand down.

But his comment is likely to be seen as adding to the growing criticism of the Speaker over the on-going row over MPs’ allowances.

Mr Martin is due to make an announcement to Parliament later today and is facing a motion of no confidence from some MPs. It is thought he may announce that he will stand down at the next general election.

Mr Green said: "Now is the time, more than ever, for the Commons to have a powerful and respected Speaker."

The continuing furore over claims made by MPs was hugely damaging to Parliament and politics, he added. "The allowances system needs a radical overhaul and a very rapid one, too. I hope Sir Christopher Kelly [chairman of the Standards in Public Life committee] can produce his report very quickly. The most important thing we need in the future is to have transparency so all expenses claims are put up as soon as they are made."

He said his own claims were now being scrutinised by the Conservatives internal watchdog committee but had no plans to bring forward details before the official publication of all MPs’ allowances next month.

The Speaker’s authority was badly undermined when Liberal Democrat leader Nick Clegg called for him to step down at the weekend.

Describing Mr Martin as a "dogged defender of the status quo", Mr Clegg said he should make way as he was not the "right man" to lead much-needed reform of Parliament.