Yvette Cooper has told Labour leadership favourite Jeremy Corbyn his plan to use Bank of England money to start a National Investment Bank to pay for infrastructure projects are "unfair" and would "fall apart".
Corbyn wants to establish a fund using money printed during quantitative easing to pay for schools and hospitals across the country. But as Thursday's leadership debate in Gateshead turned ugly, Cooper said the strategy gave the public "false hope" and that he was "not being straight with people."
Cooper urged Corbyn to abandon the economic programme if elected as leader in order to draw up an alternative to chancellor George Osborne's. "If you ditch printing money we could set out credible alternative to George Osborne," she said.
"You want to put quantitative easing in, but you are not being straight with people. It is not fair and it will fall apart." Corbyn citied Japan as an example of how the scheme would work, adding that during a period of growth "you use government bonds to fund public services."
The heated exchange came at the end of a debate that saw Cooper, Corbyn, Andy Burnham and Liz Kendall all rule out sending troops into Syria to tackle Isis. Leicester West MP Kendall said it "needed to be clear on what UK troops and air strikes would be adding to US efforts", while Burnham questioned whether bombing would simply leave a vacuum for Isis to fill.
One surprising topic of debate was the legalisation of cannabis, which Burnham, Cooper and Kendall said they could consider decriminalising. Corbyn, however, went one further, saying "we should be adult and grown up and decriminalise cannabis."
Things have got to change and the government has to act. I would get on plane to Brussels to agree a plan - on immigration crisis
I would lead a pro-EU party from day one in the interest of jobs in the north east of England and rest of country to remain in EU
My Labour principles are underpinned by "unity is strength"
The people of England and Scotland have not drifted away from Labour, Labour has drifted from them
There is a case for legalising cannabis. But it would have to be highly regulated and that presents problems
If you do bomb do you leave vacuum for Al Qaeda or Isil to fill? - on military action in Syria
The publication of Chilcot Enquiry will be a sobering moment for party.
Refugees should be termed "desperate people seeking safety"
The party needs to make strong demands to chase down approved tax havens. We need to ask strong questions about how they (the EU) treated Greeks - on the EU
We must face up to unpleasant truth that at general election we were fundamentally accepting austerity
We need to challenge the ghastly levels of inequality in society
We should be adult and grown up and decriminalise cannabis
I think the issue is we bomb, we kill and we make situation worse
Here in Britain there is an opportunity for every town and city to do their bit - on taking refugees
We have got to reform EU. It has been terrible the way Germany treated Greece
There is myth that somehow the Labour party has to choose between principles and getting into power
We need to recognise it will take time time to rebuild - on support in Scotland
We have to be part of UN, NATO and EU
we need proper local accountability so local communities can have a say over their schools
We (the UK) should be taking something like the tens of thousands. I have been ashamed. Cameron has been heartless - on migrant crisis
If we pull out if EU think of the devastation that would cause jobs, trade, inward investment. I am the strongest pro-EU candidate
Not right to spend more on servicing your debt than on educating your children - on government spending
Lets get real: the Tories want to wipe us out. The minute we have new leader they are going to throw everything at us
I think NICE is the right body to make any decisions but I think there should be proper trials - on decriminalising cannabis
We need to get away with obsession with structures in schools. What makes a great school is an inspiring head