Withdrawal from the European Union

Withdrawal from the European Union is a legal and political process whereby a Member state of the European Union (EU) exercises its right under the Treaty on European Union (TEU) to cease to be a member of the union. Withdrawal is governed by TEU Article 50, which states that: "Any Member State may decide to withdraw from the Union in accordance with its own constitutional requirements."

No member state has withdrawn from the EU, although constituent parts of two member states have have withdrawn from its predecessor, the European Economic Community (EEC). Greenland, part of the Danish Realm, voted to leave the EEC in 1985. Algeria left upon independence in 1962, having been a part of France until then.

The United Kingdom is the only full member state which has voted to leave the EU, and it remains a member while the withdrawal process is negotiated. The United Kingdom held a referendum on 23 June 2016 to decide whether it should remain a member of the European Union or leave it, which was won by the "Leave" vote. The voting results showed 51.9% voted to leave (a margin of 3.8 percent points above those voting to remain) and a voting turnout of 72.2%. Prior to this referendum, the United Kingdom had held a referendum in 1975 on withdrawal from its predecessor, the EEC; 67.2% of voters chose to remain in the Community with a turnout of 64.62%.

The Treaty of Lisbon introduced an exit clause for members who wish to withdraw from the Union. Under TEU Article 50, a Member State would notify the European Council of its intention to exit the Union and a withdrawal agreement would be negotiated between the Union and that State. The treaties of the European Union would cease to be applicable to that State from the date of the agreement or, failing that, within two years of the notification unless the Council, in agreement with the State, unanimously decides to extend this period. The two-year period of time in which the terms of the withdrawal agreement are negotiated is known as the sunset period. The agreement is concluded on behalf of the Union by the Council and must set out the arrangements for withdrawal, including a framework for the State's future relationship with the Union, negotiated in accordance with Article 218(3) of the Treaty on the Functioning of the European Union. The agreement is to be approved by the Council, acting by qualified majority, after obtaining the consent of the European Parliament. Should a former Member State seek to rejoin the European Union, it would be subject to the same conditions as any other applicant country.

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