Warning comes as Cabinet rallies round Theresa May

The EU is demanding new “concrete proposals” from Theresa May on how to end the deadlock in Brexit talks, warning that a breakthrough may not be possible without further movement from the UK.

The call from European Council president Donald Tusk came as Mrs May urged her Cabinet to “stand together and stand firm” on Brexit, after negotiations stalled in the run-up to a crucial summit.

Mrs May will address the remaining 27 EU leaders before Wednesday’s Brussels meeting, which had been billed as “the moment of truth” for Brexit but now seems certain to pass without a deal.

Speaking after being briefed by the EU’s chief negotiator Michel Barnier, Mr Tusk said he saw “no grounds for optimism” ahead of the European Council summit.

“As I see it, the only source of hope for a deal for now is the goodwill and determination on both sides,” Mr Tusk told a Brussels press conference.

“However, for a breakthrough to take place, besides goodwill we need new facts.

“Tomorrow I am going to ask Prime Minister May whether she has concrete proposals on how to break the impasse. Only such proposals can determine if a breakthrough is possible.”

Leaders of the EU27 will discuss how to step up preparations for a no-deal Brexit next March at their working dinner in Mrs May’s absence, following her presentation, he said.

Reports from Brussels suggested senior European Commission officials were casting doubt on the prospect of a special Brexit summit being declared for November if there is no movement on the key issue of the Irish border.

Mrs May won strong support from Cabinet colleagues as she set out two key “sticking points” preventing the conclusion of a withdrawal agreement.

The issues relate to the “backstop” agreement demanded by the EU to avoid a hard border by keeping Northern Ireland within the European customs area.

Mrs May has countered by offering to keep the whole UK in a customs union, but only for a temporary period.

The mammoth three-hour meeting came a day after eight Brexit-supporting ministers took the unusual step of meeting over pizzas in the office of Commons Leader Andrea Leadsom to discuss their concerns about the PM’s stance.

But despite intense speculation over a possible walkout, no minister at Cabinet indicated they might consider resigning from the Government over Brexit.

Mrs May issued a plea for unity as she said she remained determined to secure a Brexit that would respect the result of the 2016 referendum, protect jobs and security and preserve the Union.

“I’m convinced that if we as a government stand together and stand firm, we can achieve this,” she said.