What is Brexit?


On 23 June 2016, the United Kingdom (UK) voted to leave the European Union (EU). The UK leaving the EU is known as ‘Brexit’ (short for ‘Britain’ and ‘exit’).

On 29 March 2017, the UK gave notice to the European Council under Article 50 of the Treaty on European Union (pdf) of its intention to leave the EU. From this date, the EU27 (all European Union members excluding the UK) and the UK had 2 years to negotiate arrangements for the UK to leave.

This means that the UK was expected to leave the EU on 29 March 2019. This 2-year period can be extended, if the UK and the European Council agree. The European Council agreed on 10 April to extend Article 50 until 31 October 2019. This decision was taken in agreement with the UK.

On 14 November 2018, the UK and EU27 agreed at negotiator level the terms of the UK’s withdrawal from the EU (pdf) (the ‘Withdrawal Agreement’). This agreement will only take effect if it is ratified by both the UK and the EU27 – see ‘Withdrawal agreement’ below.

Negotiations on the UK’s withdrawal from the EU

Framework for Brexit negotiations

Article 50 of the Treaty on European Union requires the EU to negotiate an agreement with the member state that is withdrawing, setting out the arrangements for withdrawal and taking account of the framework for the member state’s future relationship with the EU. In April 2017, the European Council adopted a set of political guidelines which defined the framework for the negotiations and set out the EU's overall positions and principles. These guidelines stated that the EU wishes to have the UK as a close partner after it withdraws from the EU.

One of the EU’s core negotiating principles was that the withdrawal agreement had to be a single comprehensive package, with no individual matters being settled separately to the agreement as a whole. This meant that if both parties could not agree on a significant issue – such as the border between Ireland and Northern Ireland – this could undermine the withdrawal agreement as a whole.

It is important to note that the UK was a member of the European Union throughout the negotiations and that it will continue to be a member until 29 March 2019. The European Commission represented the EU27 as a whole in negotiating the UK’s withdrawal agreement. There were no separate negotiations between individual EU member states and the UK.

The Commission set up a Task Force for the Preparation and Conduct of the Negotiations with the United Kingdom, with Michel Barnier as chief negotiator.

How the Brexit negotiations progressed

The first phase of negotiations focused on the most immediate issues. The 3 priority issues were:

  • The rights of EU citizens in the UK and of UK citizens in the EU
  • The framework for addressing the unique circumstances in Northern Ireland
  • The financial settlement needed for the UK to honour past financial commitments

In December 2017, the EU and UK agreed in principle how these 3 issues would be progressed. This agreement included a commitment to avoiding a hard border between Ireland and Northern Ireland. You can read the joint report (pdf) from these negotiations.

In February 2018, the European Commission published a draft withdrawal agreement, which translated the joint report from December 2017 into legal terms. This included protocols on citizens' rights, transitional arrangements, Ireland and Northern Ireland and institutional provisions, such as the Court of Justice of the European Union.

An amended version of the draft withdrawal agreement, showing areas of agreement and disagreement using a colour-coding system, was published in March 2018.

In June 2018, the EU and UK jointly published information (pdf) about progress made in the continued negotiations on the draft withdrawal agreement.

Withdrawal agreement

In November 2018, the European Commission and UK reached an agreement at negotiator level on the entirety of the withdrawal agreement.

This document included a Protocol on Ireland and Northern Ireland, setting out a backstop arrangement to be used to avoid a hard border between Ireland and Northern Ireland. This would see Northern Ireland keep full regulatory alignment with the rules of the European Single Market and customs union. How exactly this arrangement would be implemented continues to be negotiated.

The backstop is to apply unless and until it is superseded, in whole or in part, by any subsequent agreement. If the backstop option comes into effect, the EU and UK can continue to negotiate other possible arrangements while it is in place. If both parties agree a different protocol, the new protocol will then replace the backstop arrangement.

An outline of the Political Declaration on the future EU UK relationship (pdf) has also been agreed. The EU and UK will use this outline as a basis for negotiating the final terms of the framework for their future relationship. This framework will address future cooperation in areas including trade, security, defence and foreign policy.

The withdrawal agreement also outlines the transitional arrangements to apply as the UK exits the EU, which include a transition period lasting from 29 March 2019 to 31 December 2020 (see 'Transition period after the UK leaves the EU' below').

The withdrawal agreement will only come into effect if it is ratified by both the EU and the UK.

Ratification of the withdrawal agreement

The negotiations on the withdrawal agreement must be completed by 29 March 2019, 2 years after the UK gave notice under Article 50 of its intention to leave the EU.

In November 2018, the European Council endorsed the proposed withdrawal agreement. It also approved the political declaration on the future EU-UK relationship.

For the proposed agreement to take effect, the UK must ratify it and both the European Council and the European Parliament must also vote on it.

  • The European Parliament must approve the proposed agreement by a vote of simple majority (where 15 or more member states vote in favour).
  • The European Council must then approve the agreement by a vote of strong qualified majority (where 20 or more member states vote in favour and together these states represent 65% or more of the total EU population)

If the withdrawal agreement is ratified, the EU treaties will cease to apply to the UK from the date on which the agreement enters into force.

If the agreement is not ratified, the EU treaties will no longer apply to the UK on 29 March 2019, which is 2 years after the UK’s notification of withdrawal. This situation is known as a “no-deal Brexit”. However, the European Council can decide to extend this deadline by a unanimous vote (where every member state – including the UK – votes in favour).

Transition period after the UK leaves the EU

In January 2018, the European Council agreed negotiating directives for transitional arrangements after the UK leaves the EU. The period after UK withdrawal is known as the transition period. The proposed end date for the transition period is 31 December 2020.

During the transition period the UK will remain under the jurisdiction of the European Court of Justice and stay within the single market and the customs union. All EU regulations will continue to apply to the UK, including changes made to these regulations during this period. However, the UK will no longer have voting rights in the institutions of the EU. During this time the UK can make trade deals with countries outside the EU – although they cannot come into force until 1 January 2021.

Further information

There is detailed information about Brexit on dfa.ie, including the Government’s Contingency Action Plan for a “no-deal” Brexit.

Read more in our documents Brexit and you, Brexit updates and Brexit information and supports.

Page edited: 30 May 2019