This is a timeline of major events concerning Brexit, starting from the referendum, running through Brexit day on 31 January 2020 (when the United Kingdom ceased to be a member state of the European Union), and on to 1 January 2021 (the end of the transition period). 2016 23 June: The UK holds a referendum on whether to leave the European Union. 52% of voters vote to leave. 24 June: David Cameron announces his intention to resign as prime minister. 25 June: The UK representative Jonathan Hill announces his intention to resign as an EU Commissioner. 13 July: David Cameron resigns and Theresa May accepts the Queen's invitation to form a new government. David Davis is appointed to the newly created post of Secretary of State for Exiting the European Union to oversee withdrawal negotiations. 27 July: The European Commission nominates French politician Michel Barnier as European Chief Negotiator for the United Kingdom Exiting the European Union. 3 November: In the Miller case, the High Court ruled against the Secretary of State for Exiting the European Union on the question of whether notice could be given under Article 50 of the Treaty on European Union using the Royal prerogative. 7 December: The House of Commons votes 461 to 89 in favour of Theresa May's plan to trigger Article 50 by the end of March 2017. 2017 24 January: The Supreme Court rules in the Miller case that Parliament must pass legislation to authorise the triggering of Article 50. 26 January: The UK Government introduces a 137-word bill in Parliament to empower Theresa May to initiate Brexit by triggering Article 50. Labour leader Jeremy Corbyn instructs his MPs to support it. 16 March: The bill receives Royal Assent. 29 March: A letter from Theresa May is handed to President of the European Council Donald Tusk to invoke Article 50, starting a two-year process with the UK due to leave the EU on 29 March 2019. 18 April: Theresa May announces that a general election is to take place on 8 June. 8 June: A general election is held in the UK. The election results in a hung parliament, the Conservatives remains the largest single party in the House of Commons but loses its parliamentary majority, resulting in the formation of a new minority government with a confidence-and-supply arrangement with the Democratic Unionist Party (DUP) of Northern Ireland. 19 June: Brexit negotiations