London: From the shock Brexit referendum result to this week’s crunch votes in parliament, here are the milestones on the UK’s rocky road out of the European Union after 46 years.

Britain votes to leave

In a referendum on June 23, 2016, Britons choose to end their membership of the 28-nation EU by a narrow 52 per cent to 48 per cent.

Conservative prime minister David Cameron, who called the referendum and led the remain campaign, resigns.

May becomes prime minister

Theresa May, the remain-backing interior minister, becomes prime minister on July 13.

On January 17, 2017, May sets out her Brexit strategy, saying Britain will leave Europe’s single market to allow it to control EU immigration.

“No deal for Britain is better than a bad deal,” she insists.

Exit process triggered

On March 13, Britain’s parliament approves a bill empowering May to trigger Article 50 of the EU’s Lisbon Treaty which lays out the process for leaving the union.

With a letter to EU President Donald Tusk formally announcing Britain’s intention to leave, the government starts a two-year timetable for withdrawal on March 29, 2019.

Lost majority

In a bid to strengthen her hand in Brexit negotiations, May calls a snap election for June 8, 2017.

Her gamble backfires, with her Conservatives losing their parliamentary majority. They are forced to strike a deal for support from Northern Ireland’s Democratic Unionist Party.

First terms agreed

London and the EU reach an outline agreement on December 8, 2017 on three key areas: Britain’s financial settlement to the union, citizens’ rights and the Irish border.

EU leaders green-light the next stage of Brexit talks, including on trade relations 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” and strong alignment with the EU after Brexit.

Two days later, eurosceptic Brexit minister David Davis quits, saying May is giving “too much away too easily”.

Foreign minister Boris Johnson, another key Brexiteer, follows suit on July 9.

Draft deal agreed

On November 13, May’s office says negotiators have reached a draft divorce agreement with the EU.

On November 14, her cabinet backs the agreement after hours of heated debate.

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.

Renegotiation attempt

May’s deal faces intense criticism in parliament over the “backstop” provision to prevent border checks on the Irish border.

On December 10, May postpones a parliament vote on the deal due the following day, fearing a heavy defeat, but EU leaders reject substantive renegotiation.

Leadership vote

On December 12, enough Conservative MPs are unhappy with May’s party leadership to trigger a confidence vote, but she wins by 200 to 117.

British MPs reject deal

Parliament finally votes on the withdrawal agreement on January 15.

With opposition parties and scores of Conservatives opposing it for various reasons, MPs vote by 432 to 202 against the deal - the worst defeat for a government in modern British political history.

Government survives vote

Main opposition Labour leader Jeremy Corbyn calls a vote of no confidence in the government on January 16.

The government wins by 325 to 306 votes, as May’s Conservatives rally round. She pledges to work with opposition leaders to find a Brexit breakthrough.

MPs rally behind amended deal

On January 29, British MPs vote to send May back to Brussels to renegotiate the backstop, suggesting that an amended deal could pass through parliament.

But the EU immediately says the deal is not open to renegotiation.

Week of decisive votes

British MPs voted by an overwhelmingly 391 to 242 on March 12 to reject the deal even after May and Juncker said they agreed “legally binding changes” to some of the most contentious issues.

MPs are now set to vote on March 13 on whether Britain should leave without a deal. If parliament decides no, MPs vote again vote on March 14 on postponing the departure date.