Britain is heading for a new showdown with the European Union after Theresa May bowed to pressure from UK lawmakers who demanded she renegotiate her hard-fought Brexit deal.

In a sharp reversal of policy, the British Prime Minister agreed to return to Brussels and reopen Brexit talks, even though she previously said the idea was a non-starter and the EU has repeatedly insisted the deal is locked down.

Lawmakers voted 317 to 301 to order May to seek new terms with the EU over the Irish border, a totemic issue for hardline Brexiteers that has dogged May for months. May had earlier told the House of Commons she would support the initiative, in an effort to persuade a majority of MPs to back some kind of Brexit plan.

After the vote, the EU said there was no chance of reopening the Withdrawal Agreement – signed by May in November but comprehensively rejected by the House of Commons a month later.

In a series of votes on Tuesday, lawmakers also rejected a no-deal Brexit, by 318 votes to 310. But the measure is not legally binding, and lawmakers failed to pass any plan that would have prevented the UK crashing out of the EU without a deal on March 29.

Speaking immediately after the votes, May said she would go back to the EU but admitted renegotiation with Brussels would be tough. “There is limited appetite for such a change in the EU and negotiating it will not be easy,” May told Parliament. “But in contrast to a fortnight ago, this House has made clear what it needs to agree a deal.”

To succeed, May must secure concessions within weeks on issues that have been raked over for months.

The EU showed no sign of giving in to the UK on Tuesday. A spokesman for Donald Tusk, President of the European Council, insisted that the Brexit deal “is not open for renegotiation.”

“The Withdrawal Agreement is and remains the best and only way to ensure an orderly withdrawal of the United Kingdom from the European Union,” the spokesman told CNN.

Dublin also rejected any attempt to re-open the Brexit deal. “The Withdrawal Agreement is not open for re-negotiation,” the Irish government said in a statement.

Despite saying in December that her Brexit deal was locked down, May told MPs earlier on Tuesday that she now wanted a mandate to reopen it. She argued that it would give her a chance to resolve the issue of the Northern Ireland backstop – an insurance policy to prevent the return of a border infrastructure in Ireland – despised by many Brexiteers.

But, with just 59 days to go until Britain leaves the EU on March 29, it could be too little too late. EU officials have repeatedly insisted that the withdrawal deal cannot be reopened.

One EU diplomat told CNN earlier on Tuesday: “London has negotiated with itself more than the EU. The negotiation with the EU is over.”

There are signs of deep frustration in Brussels. Guy Verhofstadt, the European Parliament’s Brexit coordinator, told CNN that the Parliament would “not give its consent to a watered-down Withdrawal Agreement.”

“The deal we have is fair and cannot be renegotiated. The backstop is needed because of UK red lines and the EU to secure the Good Friday Agreement,” Verhofstadt added.

However, it’s possible that May could secure changes to the political declaration that accompanies the deal.

It turns out that untangling a 45-year marriage after 51.9% of British people voted to leave the EU in 2016 was not as easy as some Brexiteers claimed it would be.

May’s biggest headache has been the hardline pro-Brexit lawmakers within her own Conservative party, who have opposed her deal from the start.

Unfortunately, Tuesday’s votes don’t clear much up. But one thing is for certain: the clock is ticking and unless May can get approval from both the EU and UK, or unless she seeks an extension to Article 50, the official process of leaving the EU, the UK will crash out on March 29.

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