Porn film expenses: Let Smith get back to work says Brown

The Prime Minister pleaded for the Home Secretary to be allowed to get on with her job following the disclosure that her husband used taxpayer-funded allowances to pay for adult TV films.

But the prospect of Ms Smith being demoted in a summer Cabinet reshuffle drew closer amid claims that she was "one more blunder away from the sack". As Conservative leader David Cameron called for a review into Parliamentary expenses, Health Secretary Alan Johnson was being tipped as a possible replacement at the Home Office.

MPs faced fresh embarrassment as the Commons prepared to publish the latest figures for 2007/8 expenses.

Ms Smith sparked speculation of a dressing down from Mr Brown as she walked up Downing Street today. But government sources stressed she was there for a welcome for the Mexican president before the G20 summit.

As she left her sister's south London home this morning, the beleaguered minister declined to respond to reporters' questions about the pornographic films her husband Richard Timney watched at their family home in Redditch, Worcestershire, while she was away.

Mr Brown offered his support at a Downing Street press conference today, insisting she had "done the right thing" by paying the money back.

The Prime Minister was asked whether he still had confidence in Ms Smith, who is under investigation for claiming second home expenses on her constituency house while living as a lodger with her sister.

Mr Brown said: "The Home Secretary is doing a great job and I do not think this issue should be allowed to detract from everything she is doing to ensure we protect the public and keep our neighbourhoods safe.

"She has made her apology, her husband has made clear that he has apologised. The best thing is that Jacqui Smith gets on with her work, which is what she wants to do."

No10 rebuffed calls for Mr Brown to demand a swifter review into MPs' expenses. An inquiry by the Committee on Standards in Public Life is due to start this autumn, but the Prime Minister's spokesman insisted the "timing and remit" of the investigation was purely a matter for the watchdog.

Mr Cameron said the review had to be brought forward to "disinfect" Parliament from accusations of sleaze. He said Mr Brown should implement the Conservatives' system of forcing the party's MPs to be transparent about every penny they claim from the taxpayer.

"Sunlight is the best disinfectant," Mr Cameron told GMTV. "That's what needs to happen, complete transparency about these expenses. That means the public can see what MPs are claiming and it means MPs will stop claiming for things they can't defend."

He also warned that the probe into Ms Smith's second home allowance was more of a threat to her position.

"I don't think this individual thing is the issue. I think she has got some questions to answer about her second home issue. It does seem to me incredible to claim that the home with her family is not her main home. I think that's a deeper problem," he said.

Ms Smith's political authority faced being weakened in front of her critics and her colleagues today as she struggled to get on with her job effectively at the Home Office. There was intense speculation that Mr Brown will move her after June's European and local elections, which Labour is expected to lose heavily.

Labour backbencher Paul Flynn today said she should resign because her reputation was in serious trouble from the porn film expenses claims, which "badly damaged" her.

MPs are furious that the confidential receipts were leaked to a Sunday newspaper and were meeting today to decide whether to call in the police to investigate a string of recent revelations.