Jacqui Smith revealed she is “mortified and furious” after the cost of two adult films watched by her husband were paid for out of the Parliamentary expenses budget.

The Home Secretary, who is already under investigation for her housing arrangements, will pay back the cost of the two adult films viewed at her family home in her Redditch constituency.

The £67 Virgin Media bill was submitted last June as part of Ms Smith’s expenses. It included two 18-rated features, each costing £5, which were viewed on April 1 and April 6 last year.

The bill also included two viewings of the film Ocean’s 13 - at £3.75 each - and an additional £3.50 to watch the film Surf’s Up.

Ms Smith is one of the Cabinet Ministers who could be at risk of being moved in the event of a reshuffle in June or September.

But David Miliband, the Foreign Secretary, moved to bolster the Home Secretary’s position, saying on the BBC that she was doing an “outstanding” job in one of the toughest briefs.

Ms Smith said she “mistakenly” submitted an expenses claim. A friend said the Home Secretary knew there was “no excuse” for the error but added: “To say she’s angry with her husband is an understatement. Jacqui was not there when these films were watched. She’s furious and mortified.”

Ms Smith said in a statement: “I am sorry that in claiming for my internet connection, I mistakenly claimed for a television package alongside it.

“As soon as the matter was brought to my attention, I took immediate steps to contact the relevant parliamentary authorities and rectify the situation.

“All money claimed for the television package will be paid back in full.”

But the Home Secretary was said to be “getting on with her job” today despite her embarrassment.

In a separate investigation, Ms Smith is being probed by the Parliamentary Commissioner for Standards, who said she had “fully abided” by the rules by designating her sister’s house as her “main” residence - allowing her to claim payments on the Redditch constituency home she shares with her husband and children.

John Lyon accepted a complaint about Ms Smith’s claims, and has called on her to explain the £116,000 which she has claimed since becoming an MP.

Today’s apology came as Labour left-winger Harry Cohen, who was said to have claimed more than £300,000 in second home allowances on his house in the capital, insisted that he had done nothing wrong as it was “part of my salary”.

He said that the former Conservative minister John Moore had told MPs “Go out boys and spend it” when he introduced a big uprating of the allowance in the 1980s to head off a pay revolt by backbench Tories.

The Mail on Sunday reported that the MP listed a single-bedroom schoolhouse in Colchester, Essex, and a caravan on nearby Mersea Island as his main home.

The paper said that it meant that over the past five years he was able to claim the maximum allowance of £104,701 on his constituency home 70 miles away in Leyton and Wanstead, east London.

It calculated that since 1990, he had received a total of £310,714 in allowances.

Mr Cohen said that the arrangement had been cleared with the House of Commons authorities.

Last week the Committee on Standards in Public Life announced it would be carrying out a review of the whole system.

It followed the disclosure that another Greater London MP, Immigration Minister Tony McNulty, was claiming the allowance on the home where his parents live in his Harrow constituency, even though he lived only a few miles away in Hammersmith.

However, with the committee not planning to report until after the next general election, the latest row may lead to fresh demands for an immediate crackdown.

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