Michael Howard paid £44,000 to Conservatives

The former minister made regular payments to the Folkestone and Hythe Conservative Association as part of his incidental expenses provision. In total he claimed £44,760 between 2004 and 2008.

A week ago it emerged that six members of the shadow cabinet used their office expenses to pay their party more than £150,000.

Alan Duncan, shadow leader of the House of Commons, paid £42,000 to the Rutland and Melton Conservative Association, while Michael Gove, shadow children's secretary, paid £27,000 to Surrey Heath Conservative Association.

Three Cabinet ministers were also found to have paid tens of thousands of pounds to the Labour Party through their local party associations.

Hilary Benn, the Environment Secretary, paid £30,000 rent to Labour for letting office space from his local constituency party, while John Hutton, the Defence Secretary, claimed a similar amount.

There are fears that the money could be funnelled into general accounts, which could be used to fund campaigning.

According to The Green Book of rules, MPs must avoid arrangements which may give rise to the accusation that money is being diverted for the benefit of a political organisation.

Last night Mr Howard said all office expenses paid to his local Conservative association were just, and that there was "no element of profit or benefit involved".

In September 2004, he claimed for £6,772 for his local association.

In April 2005, he claimed £9,000 for employment costs, telephone, utilities, cleaning, computers and advertising for his surgery.

A year later he claimed £9,000 for the use of the association's premises, insurance and general costs. In 2006-07, he submitted a claim for £9,990. In October 2007, he submitted claims for £4,999, and he claimed the same amount last year.

Last night, Mr Howard said: "All the payments I make to the association are to defray the costs it incurs in providing the services you mention to me. There is no element of profit or benefit involved.

"My association offices are in the centre of Folkestone.

"I hold regular advice centres there and frequently use them for other meetings with constituents and other delegations who wish to see me in my role as Member of Parliament.

"I am assisted in the performance of my duties as a Member of Parliament by the staff employed by my association and of course make use of the computer and other office equipment. The charges for advertising relate entirely to the advertising of my constituency advice centres."

Last week, Mr Duncan said there was a clear distinction between parliamentary and political costs while Mr Benn said he had sent an independent valuation of the rent to the fees office.

Yesterday, it emerged that Mr Howard had claimed more than £17,000 for "gardening services" on his second home allowance in his constituency of Kent.