British Prime Minister Theresa May got her Brexit deal with the European Union after 18 months of talks. But it looks almost certain to be thrown out when she puts it to the British Parliament Jan. 15. Overwhelming opposition to May’s deal led her to delay a vote planned for December. Where does that leave us? There are many options, including a second referendum that would let Britons reverse their historic decision of 2016, a general election, or even the outcome businesses fear most: Tumbling out of the bloc on March 29 into a chaotic limbo.

1. What has changed since December?

Not much. May said she would seek “assurances” from the EU to make the deal more acceptable to lawmakers, something she’s so far failed to do. May has offered a couple of concessions of her own, though she hasn’t impressed the politicians whose support she needs. Meanwhile, currency traders are adding to bets that the U.K. might delay its exit from the EU altogether.

2. What’s in the deal May struck?

The most important international agreement for Britain since the end of World War II sets out the terms of separation that allow the U.K. to depart the EU on March 29 in an orderly fashion, with a 21-month grace period to give everyone time to adjust. Alongside is a political declaration that specifies that the two sides want close economic and trading ties, though the details will take years to work out. As things stand, the U.K. would leave the EU’s single market, and free movement of people would end. EU citizens in Britain before Brexit would be able to stay, and vice versa.

3. Why are British lawmakers balking?

The main objection is to guarantees May has offered the EU to make sure a new physical border doesn’t emerge between Northern Ireland, which is part of the U.K., and the Republic of Ireland, which remains in the EU. Critics say the pledges -- which constitute what’s known as the “backstop” -- risk binding the U.K. to EU rules forever. They argue that May caved in to the EU and betrayed the electorate’s call to regain sovereignty, while treating Northern Ireland differently from the rest of the country. Though May survived a Conservative Party challenge to her leadership on Dec. 12, there’s still opposition on all sides: pro-Brexit hardliners in her party, other Conservatives who are pro-EU, the Northern Irish party that’s been propping up the government as well as the opposition Labour Party.

4. Will the EU offer May a better deal?

EU leaders have repeatedly said that the withdrawal agreement cannot be changed. The EU may send a letter offering reassurances about the backstop ahead of the vote in the British Parliament, but neither side thinks this will be enough to swing the result. European officials are probably waiting to see the scale of the likely defeat on Jan. 15 before deciding how to respond. The next EU summit is scheduled for March 21-22, though an emergency meeting could be called earlier.

5. Will Britain definitely leave on March 29?

Not necessarily. An extension to the negotiating period is possible, but EU leaders would have to agree to it unanimously. In private, May’s officials concede it’s a possibility, and the government’s public statements about leaving on March 29 have become more nuanced and evasive. Brexit Secretary Stephen Barclay says it’s “the government’s policy” to leave on time.

6. Who decides what happens next?

Not necessarily May. Parliament is flexing its muscle to try to change the course of Brexit, but efforts so far have focused more on avoiding a chaotic “no-deal” scenario where Britain leaves the EU without an agreement than on coming up with a clear alternative. May hasn’t said what she will do if she loses on Jan. 15, but she would have to come back to Parliament by Jan. 21 with a “Plan B.” Her Cabinet is divided on what that should be. The opposition Labour Party has said it will try to trigger a general election, though it’s not clear it will have enough support to bring down the government. May could put the deal back to Parliament again, with or without some tweaks. Or the Cabinet could decide to adopt a new approach to Brexit, in an attempt to win a majority. That would almost certainly mean trying to keep closer ties with the bloc. Other scenarios: May could call an election, or lawmakers could try to trigger a re-run of the June 2016 Brexit referendum. For now, there’s not enough support in Parliament for a second referendum, but that could change.

7. What’s a no-deal Brexit?

There’s a chance that if May’s deal is voted down, Britain would crash out of the bloc on March 29 with no agreement or grace period. That would leave the U.K. with no legal arrangements to smooth trade and other transactions with its neighbors, snarling cross-border commerce and freezing markets. Bottlenecks could bring shortages of everything from food to drugs and manufacturing components. But the no-deal scenario is probably becoming less likely as Parliament is being increasingly assertive in trying to prevent it. Lawmakers are using amendments to legislation and cross-party cooperation to try to bind the hands of the government and make it impossible for it to lead the country out of the bloc without a deal.

To contact the reporter on this story: Emma Ross-Thomas in London at erossthomas@bloomberg.net

To contact the editors responsible for this story: Flavia Krause-Jackson at fjackson@bloomberg.net, Andy Reinhardt, Leah Harrison Singer

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