Preston MP Mark Hendrick has admitted "estimating" the amount of interest he paid on the mortgage of his second home when claiming his taxpayer-funded expenses.
The Labour MP insisted that he did not accurately know how much he was paying in interest until the end of the year and so tried to "work on an average for the year".
Last year he submitted a one-off claim of 1,344.54 for "unclaimed mortgage", according to the latest MPs' expenses revelations in Wednesday's Daily Telegraph.
Mr Hendrick is also reported to have submitted regular expenses for furniture and decorating work in March – just before deadline for the MPs' second home allowance.
At one stage he wrote to Commons officials arguing that he should be paid the full 1,590 cost of a bed, which he said allowed him to "wake up in the morning without aching", unlike his previous bed.
Mr Hendrick – who this week allowed the Lancashire Evening Post one hour to review his expenses – defended his varying mortgage interest claims on his one-bedroom property in Swiss Cottage.
He told the Telegraph: "My mortgage was a capital plus interest mortgage. Therefore, payments included both, and I did not know until the end of the year from my statement exactly how much of the payment was interest, therefore I tried to work on an average for the year as a whole.
"However, at the end if each year, this was always rectified with an accurate interest figure derived from my statement."
He added: "I was trying to ascertain the correct amount and on occasions phoned my bank to work out what changes there were in interest over the months of that financial year."
He said he regularly provided the Commons fees office with copies of his mortgage documents.
Mr Hendrick "flipped" his designated second home from London to Preston after he left his post as parliamentary aide to Justice Secretary and Blackburn MP Jack Straw in 2007.
His claims for mortgage interest payments then reportedly rose to up to 1,469.
The Evening Post has already revealed how Mr Hendrick submitted claims for 3,868.87 for replacement doors, window frames, glazing and paint – a month before he changed his second home.
Other major claims for his previous London property included 1,180 for a dining table, 799.90 for a washing machine and tumble drier, 599.99 for a TV, 179.98 for a DVD player and aerial and 199.99 for a clock/radio.
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