British Prime Minister Theresa May faces a Valentine’s Day defeat in the U.K. parliament, as pro-Brexit politicians threaten to reject her Brexit strategy in a vote this evening.

Brexit-backing MPs are threatening to sabotage what the British government had hoped would be a simple re-endorsement of May’s plan to secure changes to her EU withdrawal deal, which center around a contentious plan to avoid a hard border in Ireland.

They are doing so because they are unhappy with the wording of the motion put forward by the government. The motion reiterates government support for seeking changes to the backstop, but also for avoiding a crash-out Brexit. Pro-Brexit parliamentarians object to the latter, arguing that exiting the European Union without a deal might be the best option for the U.K.

Their stance is in contrast to a growing chorus from business, with U.S. car maker Ford F, -0.59%  the latest to add its voice, according to the BBC. Ford warned it might have to cut jobs from the roster of around 13,000 people it employs in its U.K. factories if the government cannot agree a deal with the EU, which would have “catastrophic” consequences for the U.K. autos sector, it said.

This evening’s parliamentary vote is nonbinding so can be largely ignored by the British government, should the threatened rebellion come to fruition. But another parliamentary defeat will be further embarrassment for the beleaguered British prime minister, who is trying to convince EU chiefs that she can secure the backing of the majority of U.K. politicians if they agree to change the controversial Irish border elements of withdrawal agreement.

Sterling GBPUSD, -0.0156% dropped on news of another potential government defeat on Brexit, from $1.28698 at 07:40 GMT to $1.28221 at around 9 a.m. U.K. time.

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