The President of the European Council didn’t mince his words on Wednesday, saying there was a “special place in Hell” for people who “promoted Brexit” without a plan.

In an indication of just how strained negotiations between the European Union and United Kingdom have become, Donald Tusk tweeted that: “I’ve been wondering what that special place in hell looks like, for those who promoted #Brexit, without even a sketch of a plan how to carry it out safely.”

The comments drew swift condemnation from Brexiteers, with Leave campaigner and former UKIP leader, Nigel Farage tweeting: “After Brexit we will be free of unelected, arrogant bullies like you and run our own country — Sounds more like heaven to me.”

Host of Good Morning Britain, Piers Morgan, also condemned Tusk’s comments, tweeting “These EU clowns are turning me more pro-Brexit every time they open their insulting mouths.”

Irish Prime Minister Leo Varadkar, who is meeting Tusk in Brussels on Wednesday, may not have been far off the mark when a microphone picked up their private conversation during a press briefing.

“They’ll give you terrible trouble in the British Press,” the Irish Prime Minister said.

To which Tusk replied with a laugh: “Yes, I know!”

Tusk’s comments come as UK Prime Minster Theresa May traveled to Northern Ireland on a mission to seek a way forward on the Irish backstop and salvage her withdrawal agreement that has come under fire from all sides of Westminster.

Meanwhile, Tusk stressed again that the withdrawal agreement with the European Union is not open for renegotiation.

“Today our most important task is to prevent a no-deal scenario,” he told reporters in Brussels Wednesday.

“I hope tomorrow we will hear from PM May a realistic suggestion for how to end the impasse, in which the orderly withdrawal from the EU has found itself in the House of Commons,” he said.

Last month British lawmakers voted to send May back to Brussels to renegotiate the terms of the Brexit deal over concerns regarding the Irish border backstop.

The backstop — an insurance policy designed to avoid a hard border between Northern Ireland, which remains part of the UK, and the Republic of Ireland, an EU member — has been an enduring thorn in the side of May’s deal.

And it doesn’t appear to be going away anytime soon, with European Commission President Jean-Claude Juncker telling reporters in Brussels on Wednesday that the device “is not a backstop for the pleasure of having a backstop.”

“It is needed for obvious vital reasons and we cannot abandon the idea,” he said.

The clock is now ticking on Britain’s departure from the EU, set for March 29. But with Westminster standing firm on the backstop and the EU ruling out a renegotiated deal, the chances of Britain exiting the bloc without a deal at all are looking more likely than ever.

It’s a possibility the Irish prime minister said he was “increasingly” preparing for. “We don’t want no-deal, we think it can be avoided, but have to be prepared nonetheless,” Varadkar said at the Brussels meeting.