Smith's second home claim tops £22k

Ms Smith, whose claims are already under investigation by a sleaze watchdog, was battling fresh embarrassment after it emerged that public money paid for two adult films watched by her husband.

Figures released by the House of Commons show she was paid the sum in additional costs allowance (ACA), which is designed to cover the cost of working in both London and a constituency.

Ms Smith is being investigated because of complaints about her decision to designate her sister's house in south London, where she stays, as her "main" home, allowing her to claim back the costs of running her family house in her Redditch constituency.

Her overall expenses claim, including travel, office and staffing costs, was £157,631.

That sum included 25 journeys for her husband, Richard Timney, who is employed as her Parliamentary assistant, at a cost to the public purse of £2,531.

The figures released by the House of Commons authorities showed that Prime Minister Gordon Brown claimed £124,454 in expenses and allowances in 2007/08, while Conservative leader David Cameron claimed £148,829.

The details are published annually and were initially due for release last October but were delayed amid a legal row over whether full receipts and invoices should be disclosed.

MPs are permitted to claim a range of expenses, including a maximum of £23,083 for the additional costs allowance (ACA), which covers the cost of staying away from their main residence to carry out their parliamentary duties.

ACA is used to cover the cost of running and furnishing a property, as well as rent or mortgage interest payments. Most MPs use it to pay for a base in central London to use while they are working in Westminster, though some - like Ms Smith - treat their London address as their main home and claim allowances on their constituency property.