EU says UK won't get better Brexit deal if Parliament votes no

European leaders gave Theresa May her Brexit deal but warned that the UK Parliament must vote for the plan as it stands because negotiations will not be reopened if British politicians reject it.

On Sunday, the prime minister got her agreement on the UK’s divorce from the European Union at a special summit in Brussels, when the leaders of the 27 other member countries backed the legal text.

May now faces huge opposition from her own Conservative Party as she tries to persuade Parliament to back it. Even government ministers admit they have work to do to avoid defeat.

If May loses the vote in the House of Commons, which is expected to be held in December, the UK will be on course to exit the EU in March with no agreement and no transition period to cushion the blow. Some politicians want to send her back to Brussels to renegotiate if her first attempt is voted down.

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As they gathered for the summit in Brussels on Sunday, EU leaders were united in saying that the deal on the table is the best the UK will get.

“It is important that everyone in the UK is aware of the fact that this agreement is the final result,” Austrian Chancellor Sebastian Kurz told reporters. “It will definitely not be renegotiated and there will be no further leeway.”

The EU’s chief Brexit negotiator Michel Barnier issued what sounded like a warning to Tories that they need to ratify the agreement if they want the next phase of talks - focusing on the future trade terms - to go well.

“This deal is a necessary step to build the trust between the UK and the EU that we need for the next phase of this unprecedented and ambitious partnership,” Barnier told reporters. “Now it’s time for everybody to take their responsibility.”

But European Commission President Jean-Claude Juncker offered perhaps a glimmer of hope that marginal changes could be possible if May returns to Brussels asking for improvements after Parliament rejects the plan.

“It’s the best deal possible and the European Union will not change its fundamental position when it comes to this issue,” Juncker told reporters on Sunday. “I do think that the British Parliament - because this is a wise parliament - will ratify this deal.”

Euroskeptics in May’s Conservative Party hate the withdrawal agreement and are vowing to oppose it because it forces the UK to keep close to the EU’s trade rules. Many pro-EU politicians in Britain also regard it as unacceptable because the UK will not have a say over the rules it must observe.