The Tory work and pensions secretary Damian Green came under fire on Sunday morning as he was taken to task over his party's manifesto, which was described as an "uncosted black hole document".
Questioned on the Andrew Marr Show, the cabinet minister at times appeared to struggle as he was attacked over his proposed party's cuts to winter fuel allowance, and plans for social care funding.
Green called the Labour manifesto a "charade" and told Marr that Labour's policies would be funded by a "magic money tree".
But the BBC host accused the Conservatives of "double standards" in expecting Labour's manifesto to be costed, but providing no costings in its own document.
"Why does this have no costed detail at all? Why is this an uncosted document?" Marr asked, while pointing out that the Labour manifesto came with "very detailed costings".
"You mock them for the money tree and all the rest of it – they have given us quite detailed accounts of how much tax they're raise and from whom," Marr said. "You haven't."
The presenter accused the Tories of having funding "black holes" in the policy document, and asked Green to explain where an extra £8 billion for the NHS would be coming from.
"Some of our pledges are to spend less money or move money around so that it's spent in the right places", Green said in response, telling Marr the money would come from with the NHS and public services budgets.
"A lot of it is retargeting money within the system because we know we can do things better."
Green then clashed with shadow chancellor John McDonnell when the pair appeared on Marr's sofa together.
"You don't understand capitalism," Green told him. McDonnell hit back by saying "You certainly do because you made a fortune out of it" as he criticised Green for profits he made from selling shares in privatised water companies.
Hannah Al-Othman is a reporter for BuzzFeed News and is based in London.
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