A Birmingham MP has claimed more than #13,000 in travel expenses in just one year.
Khalid Mahmood (Lab Perry Barr) defended the claim as "good value for money" and said he served his constituents by travelling regularly between London and Birmingham.
Mr Mahmood's spending was revealed as MPs were forced to publish details of their #5-million-a year expense claims.
They lost a two-year battle to keep the figures secret, after they were forced to open their books under the Freedom of Information Act.
The money comes from the taxpayer and does not include expenses incurred by Ministers on official Government business, or party political campaigning.
Mr Mahmood claimed more than any other MP in the West Midlands in the year to March 2006, the House of Commons figures show. His #13,079 claim included #6,460 spent travelling by road and #6,619 in train tickets.
Staffordshire MP Paul Farrelly (Lab Newcastle-under-Lyme) claimed #12,877, including #4,828 on mileage, #8,029 on train fares and #20 on taxis.
Sion Simon (Lab Erdington) claimed #10,562, all of it spent on train tickets.
Many MPs leave their constituencies on Monday morning and stay in London until Thursday afternoon, when they return home.
But Mr Mahmood said he commuted back and forth throughout the week, and this is why his expenses were high. Mr Mahmood said: "If there is a meeting in my constituency I see it as my job to go. When we were fighting to save HP Sauce I would come to Birmingham for meetings and then set off back to London.
"Sometimes I'd leave London at 6am and travel back again at 1am the next day."
"The money doesn't go into my pocket. It is money I spend to do my job properly. I believe it is good value for money for constituents."
Although Mr Mahmood was the biggest spender overall, the MP claiming the most for using a car was Dan Kawczynski (Con Shrewsbury & Atcham).
He claimed #8,866 for driving, the highest figure in the region, as well as #870 for rail travel. Mr Kawczynski, who became an MP in 2005, said the figure was high partly because he lived in Leominster, Herefordshire, when he was first elected, and had to travel to Shrewsbury regularly.
He said: "Moving to Shropshire and being much nearer my office has resulted in the figure for 06-07 being a projected 50 per cent reduction in car mileage."
MPs can claim 40p a mile for driving up to 10,000 miles – #4,000 – and 25p per mile after that.
The MP with the lowest total travel claim in the region was Rob Marris (Lab Wolverhampton South West), who spent #2,631. This included a #36 allowance for cycling, making him the only West Midlands MP to claim for using a bicycle.
Under House of Commons rules MPs are allowed to claim 20p a mile for cycling, which suggests Mr Marris cycled 180 miles in a year.
Only three West Midlands MPs avoided driving altogether. As well as Mr Simon, they were Richard Taylor (Ind Wyre Forest), who claimed #5,874, all of it for rail travel, and Philip Dunne (Con Ludlow), who spent #3,249 on train tickets.
Tony Blair claimed the least of all the party leaders. He spent #202, all of it on car travel. Tory leader David Cameron claimed #1,823, but did not claim any expenses for cycling, despite being photographed arriving for work in the Commons on his bike.
The top ten Midlands claimers were:
Khalid Mahmood (Lab Perry Barr) #13,079
Paul Farrelly (Lab Newcastle-under-Lyme) #12,877
Sion Simon (Lab Erdington) #10,562
Paul Keetch (Lib Dem Hereford) #10,399
Robert Flello (Lab Stoke South) #10,115
William Cash (Con Stone) #10,025
Jacqui Smith (Lab Redditch) #9,935
Ian Austin (Lab Dudley North) #9,921
Daniel Kawczynski (Con Shrewsbury & Atcham) #9,736
Joan Walley (Lab Stoke North) #9,484
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