EXPLAINER: For UK and EU, Brexit has become a messy divorce

LONDON (AP) — When Britons voted for Brexit in 2016, they were promised a smooth transition to a new economic relationship with the European Union. Now the two sides are hurtling toward a tumultuous split that threatens billions worth of trade and hundreds of thousands of jobs.

An outcome almost no one wants looks increasingly hard to avoid, with U.K. and EU leaders setting Sunday as the deadline for a “firm decision” about the future of the deadlocked divorce talks, and just three weeks until the split becomes final on Jan. 1.

“Divorces are never easy,” Xavier Bettel, prime minister of EU member Luxembourg, said Thursday. “I did a lot of weddings when I was a mayor. But I also did divorces as a lawyer, and it’s always difficult.”

The messy EU-U.K. divorce has been years in the making.

WHAT WAS DECIDED IN 2016?

Britain’s 2016 EU membership referendum was dominated by whether the country should quit the bloc it had joined in 1973. What would happen after that got less attention.

“Brexit was a mandate to leave the European Union. There was never a blueprint for what did leaving look like,” said Jill Rutter, program director at the Institute for Government think-tank.

Leaders of the pro-Brexit campaign — including Boris Johnson, who is now Britain’s prime minister — said striking a new relationship with the bloc after a U.K. exit would be easy, though they provided few details. When pressed, some leading Brexit campaigners suggested Britain could have a relationship like Norway or Iceland, which have strong economic access to the EU, and in return agree to follow many of bloc’s rules and standards.

WHAT CHANGED?

Since the referendum, Brexit has come to be defined in an increasingly narrow way, largely as a result of British politics.

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