Ed Balls has unveiled a five-point plan to kick-start Britain's stalled economy in a speech to Labour's conference.
It includes a VAT cut, tax breaks for small firms and using a bank bonus tax to pay for new affordable homes and guaranteed jobs for young people.
If the coalition adopted the proposals, Labour would back it, the shadow chancellor said.
Mr Balls is trying to boost Labour's economic credibility by saying it would not reverse all the coalition's cuts.
But the Conservatives said the plan would cost £20bn and Labour was "still dangerously addicted to debt".
In his speech to Labour's annual conference, Mr Balls signed the party up to tough spending rules and vowed that any windfall from the sale of bank shares would be spent on paying off the national debt.
His five-point growth plan includes:
- Repeating the bank bonus tax - and using "the money to build 25,000 affordable homes and guarantee a job for 100,000 young people"
- Bringing forward long-term investment projects, such as schools, roads and transport, to create jobs
- Reversing January's "damaging" VAT rise now for a temporary period
- Immediate one-year cut in VAT to 5% on home improvements, repairs and maintenance
- One-year national insurance tax break "for every small firm which takes on extra workers, using the money left over from the government's failed national insurance rebate for new businesses"
Mr Balls admitted Labour had made mistakes with the economy - particularly on eastern European immigration and bank regulation - and "didn't spend every pound of public money well".
But he denied the party had been "profligate" - and launched an attack on coalition spending cuts, which he claimed were wrecking the country's chances of recovery.
Mr Balls said David Cameron and George Osborne had "the wrong prescription" for the current economic crisis, which was the "most serious in my lifetime".
The shadow chancellor said Britain's economy faced a "global growth crisis" which was becoming "more dangerous by the day".
He argued that having a growth plan would help get the economy moving again and "stop the vicious circle on the deficit" but said it wouldn't "secure our economic future" on its own and tough decisions would still be needed on tax and spending.
With the party in the middle of a two-year policy review, manifesto commitments have so far been thin on the ground in Liverpool.
But the shadow chancellor made two new pledges in his speech.
"First, before the next election - and based on the circumstances we face - we will set out for our manifesto tough fiscal rules that the next Labour government will have to stick to - to get our country's current budget back to balance and national debt on a downward path. And these fiscal rules will be independently monitored by the Office for Budget Responsibility.
"And second we know that, even as bank shares are falling again, David Cameron and Nick Clegg are still betting on a windfall gain from privatising RBS and Lloyds to pay for a pre-election giveaway.
"We could also pledge to spend that windfall.
"But we will commit instead in our manifesto to do the responsible thing and use any windfall gain from the sale of bank shares to repay the national debt. That will be Labour's choice - fiscal responsibility in the national interest."
But Treasury minister Justine Greening said the plans did not add up.
"Announcing £20bn new spending after claiming he would be tough on the deficit shows Ed Balls has zero credibility," she said.
"He's ducked all the tough decisions and refused to apologise for Labour overspending.
"Labour is still dangerously addicted to debt."