MPs who backed a law that would have blocked the public release of parliamentary expense claims are the focus of fresh revelations.
Tory David Maclean, who introduced a bill to exempt Parliament from aspects of freedom of information law, used £20,000 of taxpayers' cash to do up a property before selling it, The Sunday Telegraph has said.
Labour MP David Clelland was said to have "bought out" his partner's share of a joint mortgage at a cost of thousands of pounds to the taxpayer.
The disclosures came as Gordon Brown attempted to get a grip on the scandal with a warning that any MP found guilty of rule breaches would be axed.
Mr Brown has faced accusations of reacting too slowly to mounting public anger, with Tory leader David Cameron announcing several days ago that any of his MPs who refused to pay back sums deemed excessive by a party panel would be sacked.
The Prime Minister said: "I am appalled and angered by this week's revelations. Appalled because at all times people should expect the highest standards from people in public life. Angered because I was brought up to believe that you did the right thing - and that trust, integrity and honesty are the most precious assets of all.
"I want to assure every citizen of my commitment to a complete clean-up of the system - that wherever and whenever immediate disciplinary action is required, I will take it.
"The bottom line is that any MP who is found to have defied the rules will not be serving in my government."
Other revelations concerned other backers of the freedom of information exemption attempt for parliament, including former Labour whip Fraser Kemp. He was said to be ready to pay back money claimed for repeat purchases, including 16 sheets within seven weeks and two DVD players, admitting some claims had been an "error".
Tory Julian Lewis, who claimed more than £7,000 from the taxpayer for redecorating his second home and installing new kitchen appliances, denied any wrongdoing. He admitted the Westminster expenses system was "rotten" but insisted he had only used it to carry out essential maintenance and had not abused the system.
