Former environment minister Elliot Morley has pleaded guilty to dishonestly claiming £30,428 in mortgage payments on his parliamentary expenses.
The ex-Labour MP for Scunthorpe – who stood down from his seat in May 2009 – is Parliament’s biggest expenses cheat.
The 58-year-old is also the first ex-minister to face jail over the scandal, and had been due to stand trial.
However, he entered last-minute guilty pleas to two counts of false accounting over claims made against his home in Winterton, near Scunthorpe, Lincolnshire, between 2004 and 2007.
Morley’s false claims came after he wrongly filled out 40 forms relating to payments for his home – and saw him claiming thousands of pounds more than any of the other MPs convicted over the scandal.
He made no comment as he left Southwark Crown Court.
Campaigners have criticised him for not admitting his crimes earlier.
Emma Boon, campaign director at the TaxPayers’ Alliance, said: “It’s a shame that Morley took so long to make an admission of guilt.
“Taxpayers had to suffer the insult not only of him stealing from them, but then lying about it for so long and dragging out an expensive prosecution.”
Jim Devine, the first MP to stand trial in the wake of the expenses scandal, was branded a liar by a judge last month as he was jailed for 16 months for false claims totalling £8,385.
Two other former Labour members, David Chaytor and Eric Illsley, had already been jailed after pleading guilty to falsely claiming £22,000 and £14,500 respectively.
Former Tory peer Lord Taylor of Warwick awaits sentencing after being convicted by a jury in January of falsely claiming more than £11,000 for travel and overnight subsistence.
Morley entered his pleas as it emerged that MPs were paid £3.2m in expenses for the final two months of last year.