UK Prime Minister Theresa May suffered political humiliation in Salzburg, when European Union (EU) leaders rebuffed her appeal to give at least conditional support to her Chequers proposal for a “soft Brexit.”

May was given only 10 minutes to address EU heads of state Wednesday, after dinner at the informal summit, during which she appealed to her audience, “You are participants in our debate, not just observers.”

She said she had counted on at least supportive noises for her “serious and workable” plan, given that she was seeking to head off a potential challenge from the “hard-Brexit”/Eurosceptic wing of the Conservative Party. She warned that the UK could be torn apart—with respect to Northern Ireland and Scotland, as well as by social tensions; that if her government fell, Jeremy Corbyn’s Labour Party could win a general election; and cited the potential damage to the EU itself of lost trade, investment and military support from the UK.

Instead, her address was met with silence and her implied threats were stonewalled, as the main players within the EU combined the next day to declare her proposals to be “unworkable.”

Prior to her dinner address, European Council President Donald Tusk had rejected May’s proposal for an EU-UK free trade area covering goods and agriculture, but not services, which she claimed would eliminate the need for tariffs and border controls, especially between Northern Ireland and the Republic in the south, an EU member state. The “suggested framework for economic cooperation will not work, not least because it risks undermining the single market,” Tusk said.

May was said variously to be “staggered,” “shocked”, “humiliated” and “angry.”

Tusk laid down an ultimatum by stating that without decisive progress on the Irish border, there would be a “moment of truth” by the planned EU summit on October 18, when the Brexit negotiations are due to be finalised. If there were no such progress, he would not call the planned EU summit in Brussels November 17-18 to “finalise and formalise” a deal. “I can’t rule out the possibility of a no deal. We are not ready to compromise on our four freedoms, on our single market as well as on the Irish borders,” he said.

French President Emmanuel Macron, said to be the main author of Tusk’s hardline stance, declared at the summit’s close, “We must defend the single market and its coherence. The Chequers plan cannot be a take-it-or-leave-it plan… Brexit shows us one thing: it’s not that easy to exit the European Union. It’s not without cost. It’s not without consequences.”

The Leave victory in Britain’s 2016 EU referendum was “pushed by those who predicted easy solutions,” he added. “Those people are liars.”

German Chancellor Angela Merkel said “substantial progress” was needed on the UK’s withdrawal agreement by October and that the 27 remaining EU members were “united that, in the matter of the single market, there can be no compromises.”

European Commission President Jean-Claude Juncker said that the EU executive had prepared “in detail” for a “no deal” Brexit, “so be happy, don’t worry.”

With unattributed statements prior to the summit that the UK would be forced to retreat from Brexit during its “darkest hour,” Czech Republic President Andrej Babis and his Maltese counterpart, Joseph Muscat, openly suggested that May was no longer even considered a viable negotiating partner.

They calculate that her downfall and the likelihood of the UK parliament voting down any “hard Brexit” proposal would possibly create the conditions for a second referendum that would go in favour of Remain. Babis declared that “most of us would welcome a situation where there is the possibility of the British people putting things into perspective, seeing what has been negotiated, seeing the options, and then deciding once and for all.”

May was offered no room for manoeuvre by her Brexiteer opponents, with Jacob Rees-Mogg gloating that May’s proposals went “pop” and Democratic Unionist Party Deputy Leader Nigel Dodds insisting that preserving the “political, constitutional and economic integrity of the United Kingdom” was the “absolute priority for us.”

May relies on the 10 DUP MPs for her majority.

With nowhere to go, May reiterated, “There will be no second referendum… I think others have started to recognise rather more this is going to happen. We are going to leave the European Union.”

The Financial Times concluded: “May will be fighting to keep her plan, and possibly her premiership, alive” at the Tory Party Conference in just over a week’s time. But it too hoped that “a flurry of diplomatic activity” would follow, as “a smooth Brexit—to protect trade and diplomatic relations—remains in the interest of all parties.”

The FT also factored in the broader difficulties and tensions besetting the EU, declaring, “The Irish problem speaks to a wider challenge. Throughout the Brexit debate, too much attention has been paid to British politics—particularly the wants and whims of the Tories. But other European countries face great political challenges, too. Populist forces are on the rise from Italy to Sweden and further east to Poland. The common thread is a revolt against Brussels.”

These tensions took explosive forms at the summit, with Macron denouncing rightist governments in Italy, Austria, Hungary, the Czech Republic, Poland and Slovakia, which “don’t want to stick to humanitarian law and international maritime law and refuse to let boats dock on its ports,” blaming them for the “crisis and tensions surrounding migration.”

“Countries that are showing no solidarity will eventually have to leave Schengen and they will no longer benefit from (EU) financial aid,” he threatened.

Even so, the FT editorialised that the best that can be hoped for in the short term is a fudge in which “Vital questions about the nation’s future would be pushed into the transition period: in essence it is moving a potential cliff edge from March 2019 to December 2020.”

In the UK, the deadlock in the Tory Party is spurring on combined efforts to commit Labour to a second referendum and to remove Corbyn as party leader—whose potential premiership is anathema to the ruling elite no matter what position he takes on Brexit, because he is popularly associated with demands to end austerity and militarism.

Polls were released this week by the campaign group People’s Vote stating that Labour could win more than 1.5 million extra voters if it backed a second referendum. Led jointly by Blairite Chuka Umunna and Tory Anna Soubry, People’s Vote is holding a march in Liverpool Sunday to coincide with the start of Labour’s conference.

The conference will consider motions from more than 100 local constituency parties supporting a referendum on any final Brexit deal. The pro-Corbyn Momentum group has said it will not block such a debate.

No matter how these conflicts play out, Britain and the whole of Europe face a worsening crisis that threatens to tear the EU apart. The growth of both inter-imperialist and social antagonisms found dramatic form in Brexit, which the dominant sections of the City of London, big business, all the major parties and Britain’s allies in the US and Europe all opposed. Yet two years later, May is fighting a desperate struggle against her anti-EU “hard-Brexit” faction, the US is led by a president who has declared his support for the breakup of the EU, and numerous far-right governments have taken power in part by exploiting popular hostility to EU-dictated austerity.

Capitalism, as it descends ever deeper into trade and military war, has proved incapable of carrying out the progressive unification of the European continent. That task now falls to the European working class through a struggle against all factions of the ruling class—Leave and Remain—and for socialism.