On Tuesday, U.K. lawmakers will vote on whether to accept Prime Minister Theresa May’s plan to leave the European Union (EU).
The outcome is uncertain, particularly if May suffers defeat. Some speculate it could lead to a change of prime minister, an attempt to revise the Brexit deal, the complete collapse of government, or even a second vote on whether Britain and Northern Ireland should leave Europe at all.
May’s proposal is split into a “Withdrawal Agreement,” setting out the terms of the divorce and a “Future Relationship” document, which drafts how the U.K. will interact with the EU in the future.
The U.K. government and EU heads of state have signed off on the preliminary deal and now the British Parliament will undertake a “meaningful vote” to decide whether it can proceed.
Lawmakers will vote in the House of Commons at some point after 7 p.m. local time on Tuesday, December 11.
The government’s motion to Parliament is being intensely scrutinized before the vote takes place, with at least five full days of parliamentary time allotted to a Brexit debate.
Should it pass the House of Commons, the proposal will also need to satisfy Parliament’s upper chamber, the House of Lords.
May faces a tough task. Her deal with Europe is seen by some as a sell-out to the ideals of Brexit, reducing Britain’s influence while staying within many of the EU’s rules.
Many of those who oppose Brexit don’t like the deal either. They argue that it will reduce Britain’s ease of trade with the world, repel global talent, and increase the cost of living.
May has claimed it is the best deal she could get to satisfy a deeply divided country which in June 2016 voted 52 percent to leave and 48 percent to remain in the EU.
Her proposal now needs the backing of 320 MPs, more than half of the 639 MPs that vote in Parliament, to pass. But the numbers look tricky.
After stacking up opposing votes from the main opposition Labour party along with those from the Scottish National Party and Northern Ireland’s DUP, May is already under pressure.
Add to that the opposition from both the pro and anti-EU wings of her own Conservative Party and her Brexit deal looks in real trouble.
One estimate in The Guardian newspaper has the prime minister suffering a huge defeat of almost 200 votes. Others predict that May is still likely to lose but by a much smaller number. Any lawmakers, political analysts or media commentators who do see the deal passing are keeping quiet.