DOWNING Street has moved to defend under-fire Home Secretary Jacqui Smith after she was forced to apologise for “mistakenly” claiming the cost of watching a pair of adult movies on Commons expenses.

No 10 insisted she was doing a “great” job and would not be deflected by the latest controversy to engulf her over her Parliamentary allowances.

But, at Westminster, MPs were openly questioning whether she can save her Cabinet career.

According to friends, Ms Smith was “mortified” by the error which led to the invoice for the two films being submitted along with a £67 bill for an internet connection.

It was stressed that she had not seen the films, which were watched by her husband, Richard Timney, at their family home in Redditch, Worcestershire, while she was away.

A contrite Mr Timney appeared briefly outside the house to read a short statement apologising for the “embarrassment” he had caused to his wife.

But, while Ms Smith also apologised and promised to repay the money involved, doubts were growing at Westminster as to whether it would be sufficient to save her political career.

Angus Robertson, the Scottish National Party’s leader at Westminster, said her credibility had been undermined.