From the shock Brexit referendum result to Tuesday’s momentous vote on Theresa May’s unpopular divorce deal with the European Union, here are the milestones on Britain’s rocky road out of the bloc after 46 years.
Britons vote to leave
In a referendum on June 23 2016, Britons choose to end their membership of the 28-nation EU by 52% to 48%.
It prompts the resignation the next day of Conservative prime minister David Cameron, who had called the referendum and led the campaign to remain in the EU.
May becomes prime minister
In a race to replace Cameron, key Brexit campaigner Boris Johnson does not put himself forward as expected and May, the interior minister who had backed remaining in the bloc, becomes prime minister on July 13.
On January 17 2017, May gives a speech setting out her Brexit strategy, saying Britain will also leave Europe’s single market in order to control immigration.
She warns she would be willing to walk away from negotiations with the EU, saying: “No deal for Britain is better than a bad deal for Britain.”
Exit process triggered
On March 13, Britain’s parliament gives final approval to a bill empowering May to trigger Article 50 of the EU treaty which lays out the process for leaving the union.
With a letter to EU President Donald Tusk on March 29 formally announcing the intention to leave, the government sets Article 50 in motion.
Its two-year timetable for withdrawal puts Britain on course to exit on March 29 2019.
To capitalise on the perceived weakness of the opposition Labour party and strengthen her hand in Brexit negotiations, May calls a snap election for June 8 2017.
Her gamble backfires as the Conservatives lose their parliamentary majority. They are forced to strike a deal with Northern Ireland’s Democratic Unionist Party (DUP) to govern.
The issue of British guarantees to keep an open border between Northern Ireland and the Republic of Ireland after Brexit becomes a key sticking point in negotiations.
First terms agreed
Britain and the EU reach an outline agreement on December 8 on three key areas of the divorce: Britain’s financial settlement to the union, citizens’ rights and the Irish border.
EU leaders give the go-ahead for the next stage of Brexit talks, including on how Britain will continue to trade with the bloc after the split.
A bill enacting the decision to leave the EU becomes law on June 26 2018.
Top ministers quit
On July 6 2018, May wins agreement from her warring cabinet to pursue “a UK-EU free trade area” that would retain a strong alignment with the EU after Brexit.
But two days later David Davis, the eurosceptic Brexit minister, quits saying May is giving “too much away too easily”.
Johnson, now foreign secretary, resigns on July 9, becoming a leading critic of May’s plans.
EU leaders meeting in Salzburg on September 19 and 20 tell May that her Brexit proposals are unacceptable and need to be reworked.
Draft deal agreed
The European Union on November 13 publishes contingency plans for a “no-deal” Brexit.
But a few hours later, May’s office says negotiating teams have reached a draft agreement for the divorce.
On November 14, her cabinet backs the agreement.
However the following day four ministers, including new Brexit secretary Dominic Raab, quit in protest.
EU leaders approve the accord on November 25. “This is the only deal possible,” says European Commission President Jean-Claude Juncker.
May’s deal faces intense criticism in parliament over the “backstop” provision designed to prevent border checks in Ireland.
On December 10, May postpones a House of Commons vote on the deal due the following day, acknowledging she faced a heavy defeat.
She heads off to Europe for further talks, but EU leaders reject any substantive renegotiation.
On December 12, May’s Conservative party announces that enough MPs are unhappy with her leadership to trigger a confidence vote.
But the embattled leader survives the challenge, securing the backing of 200 Tory colleagues, while 117 voted against her.
The result meant May is immune from further internal party challenges for a year.
The House of Commons, Britain’s lower house, finally gets its chance Tuesday to vote on the draft withdrawal agreement that May struck with EU leaders in December.
With opposition parties and dozens of Conservative MPs all rejecting it for their own reason, it appears to be heading for certain defeat.
May has warned that Britain would then be entering “unchartered territory”, with the fate of Brexit itself up in the air.
Tuesday’s vote is expected from 19:00 GMT.
© Agence France-Presse