Smash hit

The Sunday Express, which reported the details, also reported that she had in fact claimed more than £150,000 in ACAs since 2001, including £1,000 for an antique fireplace, £704 for a sofabed and £550 for a Habitat stone model kitchen sink.

Mr Timney, who lives in Redditch with their two sons aged 15 and 10, is employed at public expense as a parliamentary assistant to his wife. He is likely to have filled in the claim form for the £67 Virgin Media bill, although his wife would have had to sign for it.

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

Mr Timney said yesterday that he regretted the “embarrassment” he had caused to his wife, although he did not apologise to taxpayers. Ms Smith promised to repay all the costs involved, including the £10 charge for the two films.

Last week it emerged that another government member, Tony McNulty, the Employment Minister, had claimed £60,000 in second home allowances on the house his parents live in in his Harrow constituency, even though he lived only a few miles away in another part of London.

Afterwards, Mr Brown ordered the Committee on Standards in Public Life to launch another review of the whole system of MPs’ pay and allowances.

Ms Smith, meanwhile, is already under investigation by the Parliamentary Commissioner for Standards, John Lyon, after reportedly claiming at least £116,000 in second home allowances on the Redditch house while listing a London flat she shares with her sister as her main home.

It will hardly have helped her cause that the the bill for the movies was also claimed as an Additional Cost Allowance (ACA) - which covers second homes - on the Redditch property.

Ms Smith’s career is now in the balance amid growing suspicion that she will be moved or even demoted in a reshuffle immediately before or after the summer break. Mr Brown is unlikely to take action this week, on the eve of the G20 summit. Downing Street sought to shield her, issuing a statement yesterday saying that she was doing a “great job” as Home Secretary and that would not be deflected by the latest controversy.

David Miliband, the Foreign Secretary, also described her as an “outstanding” minister, but elsewhere there was little public support, with Yvette Cooper, the Chief Treasury Secretary, carefully sidestepping the question when asked about her on Sky News.

Nevertheless friends of Ms Smith - who was said have been “mortified” by what had happened - insisted that she was determined to ride out the storm.

“She will be getting on with the job which this week is the G20. This will not distract her from doing her job,” said one.

Ms Smith said: “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 steps to contact the relevant parliamentary authorities and rectify the situation. All money claimed for the television package will be paid back in full.”

Sandra Howard, wife of the former Tory leader Michael Howard, blamed Mr Timney for "humiliating" his powerful wife and predicted that that the incident would put strain on their marriage.

"Seeing his private indulgence portrayed in such a devastatingly public way obviously undermines the very essence of a bond of trust," said Mrs Howard in a newspaper article today.

"It would be enough that she overlook his porn habit, but to skewer her career by allowing it to become publicly funded is harder to forgive. In political marriages you expect, in this digital age, unwelcome intrusion, but what your husband does when you are not there you never hope to see become political fodder."

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