LONDON - Prime Minister Gordon Brown said Saturday that any legislator in his party found to have broken rules regarding expense accounts must leave the government.

In an article he wrote for a London newspaper, Brown offered what amounted to a public apology and a strongly worded rebuke of his governing Labour party regarding a deepening scandal about questionable expense account claims that have been made by British MPs in all three top parties.

On Friday, the Labour party suspended a second member of Parliament for claiming reimbursement for non-existent mortgage payments.

Brown said he was "appalled and angered" by the revelations and said the public had the right to expect higher standards from politicians.

"The bottom line is that any MP who is found to have defied the rules will not be serving in my government," he said in an article to be published in Sunday's News of The World newspaper. "The action must be swift and comprehensive."

Brown said every expense claim made by MPs over the last four years will be investigated.

"MPs who have abused the system will have to make reparations for the past with a system of reassessment and payback," he said. "I am under no illusions that repayment will not necessarily be sufficient sanction. Unacceptable behaviour will be investigated and disciplined. I do not rule out any sanction."

Britain has seen its share of political controversies over the years, but few have tarnished all three of the country's main political parties in a single stroke.

Leaked MP expense claims for chandeliers, horse manure, pornography and moat upkeep on country estates, among other items, have enraged voters -- many of whom have lost jobs and homes during Britain's deepening recession.

David Chaytor became the second Labour MP to be punished in the scandal. Chaytor, who says he made an "unforgivable error," was suspended Saturday after he was named in the Daily Telegraph's continuing publication of previously secret expense claims.

His Labour colleague, Elliot Morley, had been suspended after admitting the same offence. An independent parliamentary watchdog is investigating both men's claims.

Members of the opposition Conservative and Liberal Democrat parties have also been caught up in the outrage across Britain about the perks enjoyed by legislators.

Chaytor had claimed reimbursement of nearly 13,000 pounds or some C$23,000 in 2005 and 2006 for a mortgage which had been paid off in 2004, the Daily Telegraph said.

"After speaking to David Chaytor this morning, the chief whip has suspended him from the privilege of membership of the parliamentary Labour party pending further investigations by the Parliamentary Commissioner for Standards," a spokesman for Brown said on condition of anonymity in line with office policy.

Chaytor said in a statement published by the newspaper that "in respect of mortgage interest payments, there has been an unforgivable error in my accounting procedures for which I apologize unreservedly."

"I will act immediately to ensure repayment is made to the Fees Office."

Chaytor's wife Sheena said he had made "a really stupid mistake."

"It was a mistake but I do not suppose anybody will believe that," she added.

There was little sympathy for Chaytor among his constituents in Lancashire.

"He should be put in flippin' jail," Press Association quoted 84-year-old Martin Flynn as saying.

"It does make me angry. Just because they are in a position of power does not mean they can get away with it," added Jessica Woods, 20.

British legislators are paid the equivalent of C$115,600, plus allowances for staff and office expenses. They are also allowed to claim expenses for maintaining homes in London and their constituencies.

Expense rules are laid out in the 66-page Green Book -- a guide sent to every legislator. It sets limits on expense claims, such as a C$45 cap on eating out when away from home and how much can be claimed toward a second home, usually a residence in London.

Though the guidelines don't ban any specific items, the rules say expenses should relate to parliamentary work and shouldn't damage Parliament's reputation.

Police and prosecutors have been meeting to decide what, if any, action should be taken against those who misused parliamentary expenses. No charges had been filed.