Image caption MPs said the Government Procurement Cards were open to fraudulent use

Tougher rules are needed to prevent the abuse of 24,000 government credit cards by civil servants, MPs have said.

A Public Accounts Committee report uncovered 99 cases of "inappropriate use" in Whitehall over the past three years, and said rules differed significantly between departments.

Some staff, it found, had used cards to pay for doughnuts, luxury hotel rooms and online iTunes purchases.

The government said the cards saved taxpayers money.

In the report, MPs called for a crackdown on those who can use the government procurement cards (GPCs), and what exactly they can buy.

The committee's chairwoman, Margaret Hodge, said current controls were "not strict enough to deter and prevent inappropriate use".

"The Ministry of Defence is by far the biggest spender, accounting for three-quarters of all expenditure using the cards, but checks only a sample of its transactions.

"We were told that this sample could be as small as 5%."

A spokesman for the MoD said it was one of the government's largest departments with more than 250,000 members of staff based around the world.

The cards cut overhead costs and gave overseas staff "speed and flexibility" to make "necessary purchases", the spokesman added.

"The MoD frequently checks up to 100% of transactions but it would be misleading to focus only on checks as all GPC spending is subject to other rigorous controls."

Alcohol ban

Mrs Hodge also highlighted the Department for Work and Pensions (DWP), which "doesn't even have receipts for a third of its transactions".

We are not convinced that this represents an appropriate use of public funds Margaret Hodge MP, Public Accounts Committee chairwoman

The GPC card system was launched in 1997 to allow public servants to pay for small purchases more easily.

MPs said that while there were "clear benefits to using the cards" - making purchases quicker and more transparent - they were open to fraudulent use.

In November, the Cabinet Office set out guidelines on minimum standards for the GPC system.

But MPs said more was needed. Departments should have to check 100% of transactions, and should extend the cards only to permanent staff members, they said.

They called for a ban on buying alcohol and a reduction in five-star hotel bookings.

Mrs Hodge added that MPs were "not convinced" the cards represented "an appropriate use of public funds".

She welcomed the Cabinet Office's promise "to produce an up-to-date business case demonstrating how cost-effective these cards are compared to other payment methods".