MPs' expenses have increased by more than �20m in two years

Staffing allowances will increase by about 8% to a basic level of �72,000, rising to a maximum of �80,460.

Commons leader Peter Hain said the extra costs were essential for MPs to function effectively.

The move comes just weeks after it was revealed that MPs' expenses had gone up by more than �20m in just two years.

According to recently published figures, backbenchers claimed an average of �118,437 in expenses on top of a salary of �57,485.

Proposing the government motion, Mr Hain told MPs: "Members' allowances have been the subject of some attention recently."

Whether we base our staff in the constituency or at Westminster is a matter for each member to determine Ann Widdecombe

It was understandable, he said, for the public to question whether these "considerable" amounts were well spent.

"But contrary to the lurid headlines these allowances do not all go to line our own pockets.

"They are essential if we are to function as effective MPs, both at Westminster and in our constituencies and all claims are within agreed rules."

The move followed recommendations from the independent Senior Salaries Review Body (SSRB) which advises the government on MPs pay and top civil servants' pay.

But MPs were angry at plans to cut their mileage allowance and early retirement pension package to bring them more in line with the rest of the public sector.

'Neutral system'

However they did vote by 193 votes to 118. to cut annual car mileage rates of 57.7p a mile for the first 20,000 miles and 26.6p after that to 40p for the first 10,000 miles and then 25p.

They will also have to pay an extra �600 a year to maintain, after inflation, the pension package they voted in during 2003.

They rejected an SSRB recommendation that only London MPs should be able to claim the full staffing allowance of �80,460.

An amendment to the government motion was passed by 239 votes to 109.

Tory former cabinet minister Ann Widdecombe argued the recommendation meant MPs were effectively being ordered to base staff in the capital.

She said: "Whether we base our staff in the constituency or at Westminster is a matter for each member to determine and the system should be neutral between the two."

Under the plans, which will come into force in April 2005, the extra allowance London MPs can claim would also be boosted from �1,618 to �2,500.

MPs will also get an increased allowance for computer and IT support.