Brexit done: United Kingdom officially leaves European Union, ending 47-year-long membership

Britain has officially left the European Union (EU), marking a historic end to its 47-year-long membership of the world's largest trading bloc.

The historic moment happened at the stroke of 23:00 GMT on Friday, more than three and half years after an in and out referendum exposed deep rifts across British society.

It also marks the start of a transition period that will last till the end of this year as negotiators try to forge a trade arrangement between Britain and the EU, Xinhua news agency reported.

While celebrations to mark "Brexit day" saw EU flags being burned on the streets of London, UK Prime Minister Boris Johnson marked the historic moment with his team at his Downing Street office, celebrating with English sparkling wine and an array of British culinary treats, Aljazeera reported.

As the clock ticked down the final seconds, thousands of Brexiters partied outside Parliament, while anti-Brexit campaigners mounted several protests along the Irish border.

In a televised address to the nation, Johnson called the UK's withdrawal from the EU "an astonishing moment of hope" .

"This is the moment when the dawn breaks and the curtain goes up on a new act in our great national drama," he said.

"And yes it is partly about using these new powers - this recaptured sovereignty - to deliver the changes people voted for. Whether that is by controlling immigration or creating freeports or liberating our fishing industry or doing free trade deals. Or simply making our laws and rules for the benefit of the people of this country.

"And of course, I think that is the right and healthy and democratic thing to do," he added. "Because for all its strengths and for all its admirable qualities, the EU has evolved over 50 years in a direction that no longer suits this country."

The Prime Minister called for "a new era of friendly cooperation between the EU and an energetic Britain".

In Scotland, which voted to stay in the EU in the 2016 referendum, rallies and candlelit vigils took place as activists sought to send a message to the EU to keep open a place for Scotland.

In Northern Ireland, the campaign group Border Communities Against Brexit staged a series of protests in Armagh, near to the border with the Republic of Ireland.

In Cardiff, First Minister Mark Drakeford said Wales would "remain a proudly European nation".

Meanwhile leaders across Europe gave their reactions to the first country leaving the EU.

German Chancellor Angela Merkel said Brexit was "a deep break for us all" and warned the "negotiations will certainly not be easy".

French President Emmanuel Macron said Brexit was an "alarm signal" for the EU and hit out at the "lies, exaggerations, simplifications" that led to the Leave vote.

The departure, 1,317 days after Britain voted to leave the bloc, carries not only enormous symbolic weight, but also significant legal consequences.

It concluded three years of fractious debates over whether the country should really leave the bloc, the terms of its departure and the kind of relationship it should forge with Europe.

Chronology of Brexit

Following is the chronology of Brexit as the UK leaves the European Union, more than three and a half years since the country voted for it in a referendum in 2016.

January 23, 2013: Prime Minister David Cameron promises an in-out referendum on EU membership if his Conservative Party wins the 2015 General Election.

May 7, 2015: The Conservatives make sweeping gains over the Labour Party and secure a majority in the House of Commons.

June 23, 2016: The UK votes in a crucial referendum to leave the EU with 52 per cent of the public supporting Brexit. David Cameron, resign as prime minister.

July 13, 2016 : Theresa May wins the Conservative Party leadership contest and becomes prime minister.

March 29, 2017 : May sends a letter to European Council President Donald Tusk, triggering Article 50. It sets the date for the UK's departure in two years' time: March 29, 2019.

April 18, 2017 : May announces a snap general election in the UK, to be held on June 8.

June 8, 2017: May loses her Commons majority after her election gamble backfires.

July 17, 2017: Brexit talks officially get underway in Brussels between EU and UK negotiators.

March 19, 2018: The UK and EU publish a draft agreement on Britain's withdrawal. But the agreement is not totally agreed.

July 6, 2018: Prime Minister May unveils to her Cabinet her much-awaited Chequers plan.

July 8, 2018: The UK's Brexit minister David Davis resigns in protest. Foreign Secretary Boris Johnson follows suit.

November 15 2018: Dominic Raab resigns as Brexit Secretary.

November 25, 2018: The 27 European Union leaders endorse the Brexit deal.

December 13, 2018: Prime Minister May survives a vote of confidence in her leadership of the Conservative Party.

January 15, 2019: MPs reject May's Brexit plans by an emphatic 432 votes to 202 in a historic vote.

March 12, 2019: MPs again reject the Government's Brexit deal by 391 votes to 242.

March 20, 2019: May asks the EU to delay Brexit from March 29 until June 30.

March 29, 2019: MPs reject May's Withdrawal Agreement by 286 votes to 344, majority 58, on the day when the UK was due to leave the European Union.

April 10, 2019: EU apress on a flexible extension to Brexit is agreed until October 31.

May 24, 2019: May announces she is standing down as Tory party leader on June 7.

June 7, 2019: May officially steps down as Tory leader.

July 23 2019: Boris Johnson is elected as leader of the Conservative Party and becomes the UK's new Prime Minister.

August 28, 2019: The UK Parliament is prorogued, or suspended, for five weeks, upon advice given to Queen Elizabeth II by Johnson's government.

September 3, 2019: 21 rebel Conservative MPs vote against the government in protest at its Brexit strategy of driving the UK towards an exit from the EU by October 31.

October 3, 2019: The UK government sends a new Brexit plan to Brussels.

October 17, 2019: The UK and EU announce dramatically that they have struck a new Brexit deal, ahead of a Brussels summit.

October 19, 2019: At a special Saturday sitting, British MPs withhold their approval for the deal until laws implementing Brexit are in place.

October 22, 2019: Johnson puts Brexit legislation on “pause”, citing MPs' obstacles.

October 28, 2019: The EU agrees to offer the UK a Brexit “flextension” until January 31.

October 29, 2019: The House of Commons approves a general election on December 12.

December 12, 2019: Prime Minister Johnson's Conservatives wins General Elections and gain an 80-seat majority in the Commons.

January 23, 2020: The UK's EU Withdrawal bill becomes law, after a relatively smooth passage through Parliament.

January 29, 2020: The European Parliament approves the Brexit divorce deal under which the UK will leave the EU on 2300 GMT on January 31.

January 31, 2020: The UK officially leaves the EU.