House of Commons Library

Brexit: how does the Article 50 process work?

Published Monday, January 16, 2017

This Commons Library briefing paper looks at the process of withdrawing from the EU under Article 50 of the Treaty on European Union. There could be a complex and difficult negotiation lasting two years or more, or the UK could leave without settling its exit terms or its future relationship with the EU.

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Article 50 TEU

The Treaty base for EU withdrawal is Article 50 of the Treaty on European Union (TEU). This is now considered the only legal way to leave the EU, although some suggested there are other ways.

Notifying intention to withdraw

After a decision to leave the EU, the first step is for the UK to notify the European Council of the UK’s intention to withdraw. There is no set timeframe for when it has to do so, or in what form.

The Government assumed notification would be done by the Prime Minister under prerogative powers. But arguments that Parliament should – or even would have to – give its consent gained currency after the referendum and became the subject of a legal challenge at the High Court and the Supreme Court in the Miller case.

There is no provision for withdrawing the notification, but many analysts believe Article 50 is revocable and that the UK could change its mind about leaving the EU after notification and before actually withdrawing. The revocability of Article 50 TEU was not raised in the Miller case before the High Court, but could be important.

The Prime Minister, Theresa May, has said the Government intends to notify the European Council by the end of March 2017.

Although UK Government ministers have talked informally to other EU leaders, the EU institutions insist there will be no formal discussions about Brexit until the UK has notified the European Council of its intention to withdraw.

The EU Commission negotiator, Michel Barnier, has been talking to other EU leaders in order to prepare the EU position on Brexit.

EU-UK negotiations

Notification will trigger the opening of withdrawal negotiations between the UK and the EU. The European Council will draw up a negotiating mandate (‘guidelines’) without the UK’s participation. Article 50 does not indicate how the guidelines will be adopted.

The EU negotiator, the European Commission, will then negotiate a withdrawal agreement with the UK. The withdrawal agreement will be concluded by the EU Council by a 'super' qualified majority (72% of participating states - excluding the UK) after obtaining the consent of the European Parliament. 

During the negotiations the UK will continue to participate in EU activities, the EU institutions and decision-making. But it will not take part or vote in any Council or European Council discussion concerning its withdrawal.

The negotiation period is two years from formal notification, but it can be extended if all Member States agree.

Member State diplomats agreed that the scheduled UK presidency of the EU in 2017 will be held by Estonia.

The withdrawal agreement

It is not clear what the withdrawal agreement will cover, but it will probably set out the detailed withdrawal arrangements and transition provisions, taking into account the framework for the withdrawing State’s future relationship with the EU.

There are particular concerns about the continuation of the UK’s trading relations with third states and there is a question about possible vested rights for individuals and companies. The UK Government has not revealed its hopes or intentions for the withdrawal negotiations. The Chancellor, Philip Hammond, has said it is likely that the UK will need a transitional agreement.

Agreement on future relationship with EU

It is not clear whether the UK’s future relationship with the EU will be covered by the withdrawal agreement or negotiated as a separate agreement alongside the withdrawal agreement.

The UK could ask to re-join the European Free Trade Association (EFTA) and the European Economic Area (EEA). Membership of these organisations would not be automatic but subject to the unanimous approval of existing Members. The Government is not looking at existing models for its future relationship with the UK, but at a bespoke agreement with the EU.

Voting on any separate post-exit EU-UK agreement could require the unanimous agreement of EU Member States and EP consent.

If the UK wanted to re-join the EU in the future, it would have to re-apply under Article 49 TEU.

Release of EU obligations on withdrawal

Withdrawal will take effect either when a withdrawal agreement enters into force, or two years after notifying the European Council of the intention to withdraw (unless there is a unanimous agreement to extend the negotiations). If there is no withdrawal agreement after two years and a veto on an extension period, or if the UK does not like the agreement, it can leave the EU without a withdrawal agreement.

The other EU Member States can reject a withdrawal agreement, but they cannot stop the UK from leaving the EU.

EU law will cease to apply to the UK upon withdrawal, but there might be some acquired rights for EU and UK citizens.

Government and Parliamentary preparations

The Government has established two new departments to manage Brexit: the Department for Exiting the European Union, with David Davis as the new Secretary of State, and the Department for International Trade, led by Liam Fox. There are two new corresponding parliamentary Select Committees: the Brexit Committee, chaired by Hilary Benn, and the International Trade Committee, chaired by Angus Brendan MacNeil.

Dealing with EU law the UK has implemented: the 'Great Repeal Bill'

On 2 October 2016, the Prime Minister announced plans to introduce a “Great Repeal Bill” in the next Queen's Speech, which will repeal the European Communities Act 1972 (the ECA) and incorporate (transpose) European Union law into domestic law, “wherever practical”. The Government has indicated that these legal changes within the Bill would take effect on “Brexit Day”: the day the UK officially leaves the European Union (EU).

The Government has indicated that the Bill will be designed to re-establish control over law-making by repealing the ECA and to provide some certainty over the content of the statute book while the UK negotiates its exit from the EU. Once the UK has left, the next legislative stage would be for Government and Parliament to decide whether to keep any EU-derived law in UK domestic law.

The devolved regions

The devolved legislatures will have to deal with EU legislation they have transposed into Scottish, Welsh or Northern Irish law. It will also be necessary to amend the relevant parts of the devolution legislation, which might require a Legislative Consent Motion under the Sewel Convention.  This is discussed in more detail in CBP 7793, Legislating for Brexit: the Great Repeal Bill, 21 November 2016.

Commons Briefing papers CBP-7551

Authors: Vaughne Miller; Arabella Lang; Jack Simson Caird

Topics: Central government, Constitution, Crown, EU external relations, EU law and treaties, Europe, International law, International organisations, Legislative process

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