David Cameron was under pressure to ensure the probity of his MEPs last night after forcing the resignation of the Conservative party’s leader in Europe over an expenses scandal.

Mr Cameron welcomed publicly the decision of Giles Chichester the MEP who admitted to breaking European Parliament rules by channeling £445,000 of allowances through a family company.

His position was viewed as untenable partly because he had been given the job of a sleazebuster by Mr Cameron to ensure the integrity of Tory MEP expenses.

Mr Chichester’s decision to quit followed a day of furious behind-the-scenes exchanges as Conservative central office insisted on his departure. Mr Cameron’s senior officials were desperate to prevent a resurgence of headlines about Tory sleaze that could damage the party’s commanding lead over Labour.

Mr Chichester, 61, was stripped of his leadership job after admitting on Tuesday that he broke the rules by paying his allowances through Francis Chichester Ltd, a map company founded by his late father, the round-the-world yachtsman.

He did not help his case by apparently making light of it. “It is embarrassing not least because I have introduced a new code for my Conservative colleagues for expenses. Here I am leading that process for the last couple of months and — whoops a daisy — I am shown up to have made a mistake. OK, hands up, mea culpa, and I will put it right,” he told ITV Westcountry.

Mr Chichester faced more questions yesterday from The Times, not least how he could account for paying himself £5,000 a year in rent from the company for a Mayfair property that he owns, and how much he and his wife received as the company’s only paid directors.

There was criticism last night of Mr Cameron’s decision to allow him to remain a Conservative MEP and fight the next European election in 2009. Mr Chichester was reselected earlier this year to stand again in his constituency of the South West of England and Gibraltar. Mr Cameron’s next test will be trying to exert control over his 28 MEPs in Brussels who have a reputation for defying the London party and causing headaches for successive party leaders.

Last night the spotlight was also cast on Den Dover, MEP, the Conservative Chief Whip in Brussels, after he recently admitted paying his entire European Parliament expenses to a company run by his wife and daughter. A Conservative spokesman said that Mr Dover had assured the party that there had been no misuse of public funds.

Mr Chichester left the European Parliament last night heading for his London home without making a comment to The Times, but issued a resignation statement after leaving the building. “I apologise once again for the fact that I have been in breach of the parliamentary rules, he said.

“I wish to allow myself the space to prepare my report to the parliamentary authorities and demonstrate that monies were properly spent and accounted for.”

Although MEPs are encouraged to set up companies to handle their office and staff expenses, Mr Chichester is understood to have been told earlier this week by parliamentary officials that he had broken the conflict of interest rule that prevents MEPs from benefiting or seeming to benefit from those companies. A detailed inquiry by the Parliament will decide if he has to repay some of the cash.

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