A comprehensive review on MPs' pay and perks has been brought forward and will now be completed by the end of the year, Westminster's main sleaze watchdog announced today.

The Committee on Standards in Public Life had not originally planned to release its recommendations until after the next election, due by May 2010, but was asked by party leaders to speed things up after a slew of damaging expenses scandals.

Gordon Brown, the Prime Minister, last night appealed to Sir Christopher Kelly, the Committee's chairman, asking him to expedite the inquiry and suggesting that the system might near far-reaching reform, including the abolition of a "second home allowance".

The last straw appears to have been the revelation that Jacqui Smith, the Home Secretary, submitted a claim that included two pay-per-view pornographic movies watched by her husband, Richard Timney.

Ms Smith already faces an investigation by a Commons watchdog over her decision to declare her sister's house in London - where she has a room - as her main residence, allowing her to claim more than £100,000 in second home allowance for her family home in Redditch.

In a statement released today, Sir Christopher said it was “now obvious” that a quicker probe was needed and that they would suspend other work and begin an “independent, wide-ranging” review straight away.

“The situation has changed quite dramatically over the last few months and I am pleased that there is now such widespread political consensus on the need for reform,” he said.

“I hope that this will translate into full acceptance of our recommendations by all the main political parties - challenging though they are likely to be.”

He went on: “The issues involved are complex. We will be meeting with party leaders and intend to publish an Issues and Questions Paper within the next few weeks. We will ask for written submissions from all interested parties and hold a number of public hearings. All evidence submitted to the inquiry will be published.

“This is not something which can be done with a quick fix; we want to do a thorough piece of work. Our firm intention is to publish our report towards the end of the year.”

News of the review came as Commons officials sought to track down a "mole" alleged to have put explosive details of MPs’ expenses on the market for £300,000. Sir Stuart Bell, a veteran Labour MP and member of the House of Commons Commission, said that they had “a pretty good idea” of the source of the leaks, but not any individual person.

A series of damaging leaks, concerning claims by Ms Smith and Tony McNulty, the Employment Minister among others, have stoked public fury over generous parliamentary perks. Both ministers are under investigation over their use of second-home allowances.

That anger was fuelled further yesterday when it was disclosed that MPs will get a 2.33-per cent pay rise next year - as millions of private sector workers face freezes or even cuts - and that the total taxpayer bill for allowances in 2007/8 had risen by six per cent in a year to £93 million.

More than 150 MPs received the maximum £23,083 in Additional Costs Allowance to cover the cost of staying away from home on parliamentary business. Ms Smith was paid £22,948.

Downing Street said yesterday that Government ministers would not enjoy any pay rise this year - a move followed by the Conservatives and Liberal Democrats. It emerged today that MPs are also to be asked to pay more in pensions contributions to help reduce a deficit in the scheme.

Money Central: the 10 most outrageous MP expense claims ever

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