David Cameron has vowed to make Leave campaigners like Boris Johnson "pay" for their claims about Britain's economic prospects outside the European Union.
Pledges made by London's former mayor and Michael Gove that the UK will strike up a series of swift and lucrative international trade deals if voters back Brexit in the June 23 referendum are "nonsense on stilts", the Prime Minister said.
In an interview with the Mail on Sunday, he said: "Their argument is, 'Let's wreck the economy by leaving the single market in order to do it'.
"I'm going to make them pay for that.
"The idea that the world just gives you great trade access is nonsense on stilts. Boris wants us to be like America, so you'd be subject to WTO (World Trade Organisation) tariffs on cars, clothes, shoes.
"It's common sense: if you cut yourself off from your biggest market your economy will be poorer – and they know that."
Mr Johnson, who attends political Cabinet, the Justice Secretary, employment minister Priti Patel and other senior Tories who have set their face against the premier, will not be sacked," the PM said.
"No. We have to bring the party back together. I've always believed in having the big players on the pitch," he said.
Mr Cameron underlined his frustrations with Brussels, telling the newspaper: "You've got people who are p***** off with some of things it has done. I understand that: I'm one of them."
In a revealing insight into how the referendum campaign is playing out at home, Mr Cameron said wife Samantha "sees the Leave argument as very backward-looking, trying to recreate something that isn't there any more".
Daughter Nancy, 12, has also thrown her support behind the Remain campaign. He said: "She wants to know how it's going and thinks In is the right answer.
"She has strong views. She is very green, always quizzing me on solar panels and flood defences."