Prime Minister Theresa May urged the European Union on Friday to make “just one more push” to break the deadlock over Brexit by offering her changes to a deal to help persuade Britain’s deeply divided parliament to approve it.

With just three weeks left before Britain is due to leave the European Union, May has failed so far to get the changes to her divorce deal that she believes would win over lawmakers who handed the government a defeat of record proportions in January.

In a last-ditch appeal to the EU and to lawmakers at home, May spoke in the northern English port town of Grimsby to say it was time to end the uncertainty over Brexit and approve the deal on Tuesday.

Warning that lawmakers could risk putting Britain’s departure into doubt or triggering many more months of arguments over Britain’s biggest shift in foreign and trade policy for decades, May had a simple message: “Let’s get it done.”

“It needs just one more push to address the final, specific concerns of our parliament,” May told her audience in Grimsby, where 70 percent voted to leave the EU in the 2016 referendum.

“So let’s not hold back. Let’s do what is necessary for MPs (members of parliament) to back the deal on Tuesday,” said May, who at the end was criticized by a woman journalist for allowing so few female reporters to ask questions on Women’s Day. May replied: “You’ve had answers from a woman prime minister.”

London and Brussels are at loggerheads over the so-called Northern Irish backstop, an insurance policy to prevent the return of border controls between Northern Ireland and Ireland – the only land frontier between the United Kingdom and the bloc.

“Sign of Desperation”

Under pressure from some lawmakers in her own Conservative Party, May wants legally binding assurances from the EU that Britain will not be trapped permanently in the backstop, which would keep Britain in a customs union with the bloc.

Asked if she was responsible for the uncertainty that has forced many businesses to put off investment decisions, May again said there was only one way to ease their concerns – and that was to vote for her deal and move on.

Otherwise, she said Brexit might never happen and voters would be betrayed. Or, she added, Britain could leave without a deal to soften the shock, a nightmare scenario for many companies.

Those arguments largely restated her well-worn line. Eurosceptics say her agreement does not offer a clean break with the EU, while EU supporters want to maintain closer ties.

Jeremy Corbyn, leader of the main opposition Labour Party, said the appeal was “more like a sign of desperation.”

“These are very serious times. We don’t need any more delays and dithering by the government,” he told Sky News. “They’ve got to recognize her deal isn’t going to work, it doesn’t get support, and will not get through parliament.”

It was the first time that May had turned directly to the EU, showing signs of frustration that talks to secure changes to the backstop this week had as yet produced no breakthrough.

That frustration was matched on the EU side. Irish Prime Minister Leo Varadkar said the British, not the EU, had to compromise, and the decision to leave the bloc had been “a problem of their own creation.”

Blame Game?

EU diplomats, responding to excerpts of May’s speech released overnight, said she was preparing to blame the bloc for a fresh defeat of her plan.

“We are expecting a blame game after she loses the second ‘meaningful vote’ next week, so it looks like she is already preparing the ground for this,” one of the diplomats said.

May desperately wants her plan to pass in parliament on Tuesday. If it is defeated, lawmakers will be able to vote on Wednesday and Thursday on whether they want to leave the bloc without a deal, or ask for a delay to Brexit – all but wresting control of Brexit from the government.

In a last-minute flurry of diplomatic activity, May was due to speak to EU leaders by telephone over the weekend and a European Commission spokesman said “intensive work” was going on between London and Brussels.

Attorney General Geoffrey Cox, charged with negotiating the changes to the deal, or another member of the government, could travel to Brussels on Saturday or Sunday if the talks progress.

Foreign minister Jeremy Hunt held out some hope that a deal was “entirely possible” in time for the vote.

“We want to remain the best of friends with the EU; that means getting this agreement through in a way that doesn’t inject poison into our relations for many years to come.”

(Additional reporting by Alistair Smout, James Davey and Joe Green in London, Conor Humprhies in Dublin and Gabriela Baczynska in Brussels; writing by Elizabeth Piper and William Schomberg.)