Transport Secretary, Ruth Kelly, formerly Tony Blair’s controversial choice as Equality Minister has been forced to apologise after misspending taxpayer’s money on Labour party publicity.

MPs are allowed to spend £10,000 of public funds on neutral leaflets but are not allowed to use them to make party political statements.

A newsletter published this Autumn distributed to constituents in Ms Kelly’s marginal Bolton West seat and paid for from her allowance, repeatedly refereed to ‘Labour’, ‘Labour Party’ and ‘Labour Government’.

Ms Kelly told the Mail on Sunday: “There was no intention to do anything other than comply with the rules. However, I accept that greater care should have been taken over the exact wording, for which I unreservedly apologise.

“I will contact the Serjeant at Arms at the earliest opportunity and will, of course, abide by his decision on this matter.”

The minister may now be forced to repay the funds used on the leaflets.

Mrs Kelly has a slim majority of 2,000 over the Conservatives. If, as expected, an Election had been called last month she was at risk of losing her seat.

The newsletter came out around the time that speculation was at its most intense.

The Conservatives have written to the Serjeant at Arms, a parliamentary watchdog, asking him to investigate.

“The allowance should only give non-political facts about the work of an MP,” said David Davies MP.

“It looks like Ruth Kelly has breached the rules and, if this turns out to be the case, the public will be outraged that their money is being used for party political purposes.”

If the Serjeant at Arms believes the breach is serious, Mrs Kelly could be referred to the Commissioner for Parliamentary Standards and ordered to repay the money.

Fellow Labour MPs; Bridget Prentice, Gisela Stuart and Julie Morgan were also accused by the Conservative Party of adopting similar practices.

Francis Maude, Shadow Cabinet Office Minister commented: “The Communications Allowance was deliberately created to enable sitting Labour MPs to protect themselves against their democratic opponents.

“This is further evidence of how Labour voted through taxpayers’ cash to bankroll their political campaigning in marginal seats. If Gordon Brown is serious about restoring trust in politics, he should scrap this unfair allowance now.”

Ruth Kelly’s appointment as Equalities Minister last year, having never voted in favour of gay rights legislation, was highlighted by PinkNews.co.uk. She was later moved to the less controversial role of Transport Secretary by Gordon Brown.