THE deep divisions in the UK Cabinet over Britain’s EU withdrawal have been laid bare yet again by Boris Johnson who was secretly captured warning of a Brexit “meltdown” and branding the Treasury the “heart of remain”.

In unguarded comments at a private dinner, the Foreign Secretary said there was a risk Brexit "will not be the one we want" and would keep the UK "locked in orbit" around the EU.

At the gathering of the Conservative Way Forward, a Thatcherite campaign group, he accused Chancellor Philip Hammond’s Treasury of being the "heart of Remain" and claimed negotiations were approaching a "moment of truth".

In comments captured in a recording obtained by BuzzFeed News, he said Prime Minister Theresa May was "going to go into a phase where we are much more combative with Brussels".

He added: "You've got to face the fact there may now be a meltdown. OK? I don't want anybody to panic during the meltdown. No panic. Pro bono publico, no bloody panic. It's going to be alright in the end."

Mr Johnson suggested the UK could end up "in the customs union and to a large extent still in the single market".

The Cabinet minister was speaking to around 20 people dining in a private room after a reception at the Institute of Directors on Wednesday night.

He said: "Unless you make the change, unless you have the guts to go for the independent policy, you're never going to get the economic benefits of Brexit. You'll never get the political benefits of Brexit."

Mr Johnson said fears about the border on the island of Ireland were out of proportion.

"It's so small and there are so few firms that actually use that border regularly, it's just beyond belief that we're allowing the tail to wag the dog in this way.

"We're allowing the whole of our agenda to be dictated by this folly."

The Foreign Secretary also suggested Donald Trump would "go in bloody hard" and "might get somewhere" in the exit talks if he was in charge.

Lord Howard, the former Tory leader, sought to downplay Mr Johnson's warning of a Brexit "meltdown,” saying it was all part of the "spills and thrills" of EU withdrawal negotiations.

Asked about Mr Johnson's claim that officials in the Treasury were working against the long-term gains of Brexit, the Tory peer said: "If there are people in the Treasury who are doing that then they shouldn't be doing that, and I deplore that."

Scottish Labour’s Ian Murray MP, a leading supporter of the People’s Vote campaign, said: “Boris Johnson is utterly shameless. As these comments show, he knows we're going to get shafted with a bad Brexit deal, he knows how much damage it will cause to our economy, he knows it will result in a hard border re-emerging in Northern Ireland, but he couldn't care less.”

Branding the Secretary of State a “disgraceful charlatan,” the Edinburgh MP claimed he was a constant source of embarrassment and shame and cared about “nothing except himself and his own ambition”.

Mr Murray added: ““He is right about one thing: we are heading for ‘a meltdown’ over Brexit. But his solution is simply to embrace the chaos.

“Rather than continuing to let this Donald Trump tribute act determine the future of our country, we should take back control by having a People's Vote on the final Brexit deal.”