MPs who fiddle their expenses could face up to a year in prison under Government proposals published last night and aimed at cleaning up the system of parliamentary allowances.

The Parliamentary Standards Bill will establish a new independent body to administer MPs’ pay and allowances, with a Commissioner for Parliamentary Investigations to probe alleged breaches of the rules.

It will also create a series of new criminal offences, including knowingly providing false or misleading information in a claim for an allowance.

That would incur a maximum penalty of 12 months in prison or an unlimited fine.

MPs who fail to register properly their outside interests will face a fine of up to £5,000, as will any MP who breaches the rules on paid lobbying.