Withdrawal from the EU

Withdrawal from the European Union is the legal and political process whereby a member state of the European Union ceases to be a member of the union. Member states have the right to withdraw from the Union under the Treaty on European Union (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No member state has withdrawn from the EU, although constituent parts of two member states have withdrawn from its predecessor, the European Economic Community (EEC).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. On 29 March 2017, the UK gave formal notice (in accordance with Article 50) of its intent to withdraw, beginning the two-year negotiation period.

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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