Labour will try to reverse George Osborne's decision to cut the top rate of income tax today, as it appeals to Tories and Liberal Democrats to reject their own Budget.
After weeks of negative headlines, Labour is seeking a U-turn on a host of Budget proposals, including the 50p top rate, the tax on pasties and caravans and the cap on tax relief on charitable donations.
"George Osborne's Budget has unravelled with every passing day," said shadow chief secretary to the Treasury Rachel Reeves.
"It's unfairness and lack of plan for jobs and growth have been exposed.
"We are calling on Liberal Democrat and Conservative MPs who fear that George Osborne has got things badly wrong to join us in standing up for households and businesses."
She added: "For those businesses and employees whose livelihoods have been thrown into doubt by the government's chaotic changes to VAT we will seek to vote to force the government to think again on their VAT hikes on hot food, static caravans and on improvements to listed buildings like churches."
The Budget triggered a spate of bad headlines for the government – even in normally loyal sections of the press – and seriously damaged Mr Osborne's reputation as a master strategist.
It also bulked up Labour's lead over the Conservatives in the polls and saw the Liberal Democrats drop into fourth place, behind Ukip.
Labour's appeals to Tories and Lib Dems rarely succeed, however. An attempt to cooperate over cuts to legal aid last night came to nothing when Liberal Democrats rebels refused to back their amendments to the legal aid, sentencing and punishment of offenders bill.
However, Cornish MPs from the governing parties have raised the prospect of cooperating with Labour MPs from northern 'meat and potato pie' constituencies to shoot down the pasty tax proposals.