A Birmingham Labour MP has published her own proposals for dealing with the 10p tax rate fiasco, in a further sign the Government has failed to end the row.
Lynne Jones (Lab Selly Oak) called on the Government to ensure there were no losers from the controversial reforms, as Gordon Brown fought back against critics.
Former Minister Frank Field, who led the backbench revolt over the abolition of the 10p income tax rate, said he would be "very surprised" if Mr Brown was still in charge at the time of the General Election, expected in 2010 - and suggested the Prime Minister should talk to his family about stepping down.
But Children's Secretary Ed Balls, Mr Brown's closest ally, was despatched to launch a scathing counter-attack, as Labour's civil war threatened to spiral.
Dr Jones set out her proposals in a Commons motion calling for taxpayers to be offered a choice between paying under the old system or the new.
The 2007 Budget, presented by Mr Brown when Chancellor, cut the basic rate of income tax from 22p to 20p, but doubled the lowest rate from 10p to 20p.
It meant many on low incomes - who didn't earn enough to benefit from the cut in the 22p rate - saw tax bill rise, although in many cases this was offset by increases in tax credits.
Dr Jones said taxpayers should be allowed to move back to the old tax rates of 10p and 22p, ensuring nobody on a low income was forced to pay more tax.
She said: "There are now a number of ideas as to how we can ensure people on low incomes are not made poorer by tax changes. We need an indication from ministers yes, everybody affected is going to be compensated."
Despite her concerns, Dr Jones said she was "disgusted" by the behaviour of Labour MPs who had attacked Gordon Brown.
She said: "Some of the people that are now being very disloyal, it is as if the don't really care about winning the next election. I don't think I have ever been so disgusted."
Mr Balls suggested Mr Field was not seriously interested in dealing with problems caused by the tax reforms.
He said: "I think it is very unlikely on the basis of what I have seen that Frank Field will support any proposals that are brought forward by Government on the 10p tax."
Asked if Mr Field was trying to "take down" Mr Brown, the Children's Secretary said: "I'll leave you to draw your own conclusions from what was said this morning."
The Prime Minister will try to get his premiership back on track tomorrow with the publication of a draft Queen's Speech.
This is expected to include a review of social care, and reforms to employment law extending the right to request flexible working to parents of children under 12.
Other initiatives will include measures to tackle binge-drinking and failing schools, and to expand shared equity schemes to help first-time buyers.