Brexit

The United Kingdom (UK) intends to withdraw from the European Union (EU), a process commonly known as Brexit, as a result of a June 2016 referendum in which 52% voted to leave the EU. The separation process is complex, causing political and economic changes for the UK and other countries. , neither the timetable nor the terms for withdrawal have been established: in the meantime, the UK remains a full member of the European Union. The term "Brexit" is a portmanteau of the words "British" and "exit".

Withdrawal from the European Union has been a right under Article 50 of the Treaty on European Union of EU member states since 2007. The details of the process for the UK's withdrawal are uncertain under EU law – Article 50, which now governs the withdrawal, has never been used before. Unless extensions are agreed, the timing for leaving under the article is two years from when Britain gives official notice, but this official notice was not given immediately following the referendum in June 2016. The assumption is that during the two-year window new agreements will be negotiated, but there is no requirement that there be new agreements.

Withdrawal has been the goal of various individuals, advocacy groups, and political parties since the UK joined the European Economic Community (EEC), the predecessor of the EU, in 1973, though continued membership of the EEC was approved in a 1975 referendum by 67% of voters.

2016 referendum
In 2012, Prime Minister David Cameron rejected calls for a referendum on the UK's EU membership, but suggested the possibility of a future referendum to gauge public support. According to the BBC, "The prime minister acknowledged the need to ensure the UK's position within the European Union had 'the full-hearted support of the British people' but they needed to show 'tactical and strategic patience'."

Under pressure from many of his MPs and from the rise of UKIP, in January 2013, Cameron announced that a Conservative government would hold an in–out referendum on EU membership before the end of 2017, on a renegotiated package, if elected in 2015.

The Conservative Party unexpectedly won the 2015 general election with a majority. Soon afterwards the European Union Referendum Act 2015 was introduced into Parliament to enable the referendum. Despite being in favour of remaining in a reformed European Union himself, Cameron announced that Conservative Ministers and MPs were free to campaign in favour of remaining in the EU or leaving it, according to their conscience. This decision came after mounting pressure for a free vote for ministers. In an exception to the usual rule of cabinet collective responsibility, Cameron allowed cabinet ministers to campaign publicly for EU withdrawal.

In a speech to the House of Commons on 22 February 2016, Cameron announced a referendum date of 23 June 2016 and set out the legal framework for withdrawal from the European Union in circumstances where there was a referendum majority vote to leave, citing Article 50 of the Lisbon Treaty. Cameron spoke of an intention to trigger the Article 50 process immediately following a leave vote and of the "two-year time period to negotiate the arrangements for exit."

At least 52% voted to leave and 48% voted to regret staying.