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Explainer

Brexit transition period

The Brexit transition is the period in which the UK is no longer a member of the EU but remains a member of the single market and customs union.

What is the Brexit transition period?

The Brexit transition is the period agreed in the UK–EU Withdrawal Agreement in which the UK is no longer a member of the EU but remains a member of the single market and customs union. During that time, it will continue to be subject to EU rules. The transition period started immediately after the UK left the EU on 31 January 2020.

The UK government does not use the term transition: instead it prefers to refer to this period as an “implementation period”.

Why does the UK need a transition period?

The EU said it will not negotiate details of new arrangements with the UK until it ceased to be an EU member. The transition period is designed to provide time for that new relationship to be agreed while ensuring that business will only need to adapt to non-EU rules once the future deal is agreed.

How long is the transition period due to last?

The Withdrawal Agreement specifies that the transition period will last until 31 December 2020. That end-date was included in Theresa May’s original Withdrawal Agreement. If this deal had been approved by parliament, then it would have allowed 21 months for the completion and ratification of negotiations on the long-term relationship. The subsequent delays to the UK's withdrawal from the EU will mean that the transition period will now last for 11 months.

The terms of the Withdrawal Agreement allowed the UK–EU Joint Committee to extend the transition period by up to two years if it signed off on the length of any extension before 1 July 2020. However, the UK and the EU did not choose to extend. EU lawyers say that once that window is missed, EU law makes it very difficult to agree to any extension.

The government has ruled out any extension to transition and legislated for a commitment not to agree to any extension in the Withdrawal Agreement Act. The government is only able to reverse that provision through new legislation.

What are the differences between the transition period and EU membership?

The UK ceased to be a member of the political institutions of the EU on 31 January 2020. There are no UK MEPs in the European Parliament, no UK commissioner and UK ministers no longer attend meetings of the European Council. Everything else has remained the same.

What has stayed the same?

The UK is still part of the EU’s economic institutions and security co-operation arrangements until the end of the transition period. During this time, the EU has continued to treat the UK as a member of the single market and customs union. It has also asked its trade partners to continue to treat the UK as a member state until the end of transition.

Freedom of movement remains in place and citizens’ rights continue unaffected until the end of the period.

The UK remains be subject to EU law and the rulings of the European Court of Justice throughout the transition period.

On security, the UK continues to have access to EU mechanisms (like Europol) and databases; but some EU countries like Germany cannot extradite their citizens using the European Arrest Warrant to countries that are not member states of the EU. Therefore, they cannot extradite them to the UK during the transition period.

What will change at the end of the transition period?

At the end of transition, the UK’s relationship with the EU will be determined by the new agreement it has negotiated with the EU on trade and other areas of co-operation. The Conservative manifesto suggested it was aiming for a relatively loose free trade agreement that would see Great Britain leave the single market and the customs union – and did not mention anything on security co-operation.

In a no-deal scenario, the UK would have to rely on previous international conventions for security co-operation and would trade with the EU on World Trade Organization terms. The exception in both these cases is Northern Ireland, whose trade in goods with the EU would be covered by the provisions in the Northern Ireland protocol.

Even without a deal, the UK would continue to follow the EU rules transferred into UK law through the EU Withdrawal Act 2018. At the end of transition period, the UK would be able to diverge if UK courts decided to interpret existing EU law differently or if the government introduced changes into UK law.

Is it feasible to get new EU–UK arrangements in place by December 2020?

Implementing the Withdrawal Agreement provisions, as well as preparing for the future relationship by the end of the transition period, requires strengthening border capabilities, creating and modifying public bodies, making significant changes to immigration rules, as well as supporting business to prepare.

This is a huge task, particularly considering the 11-month time frame the government has to negotiate and implement a new deal. It is likely the UK will be only partially ready by the end of December 2020.

In some areas, the UK government has announced unilateral measures that delay the need to have all arrangements in place. This includes the phasing in of customs checks on EU goods coming into the UK.

Does no agreement mean the same outcome as a no-deal Brexit in March or October 2019?

No. No deal on the future relationship would still leave the Withdrawal Agreement in place: citizens’ rights would be protected, the UK would still be committed to the financial settlement and Northern Ireland trade would be covered by the protocol.

But for the rest of the UK, trade and security co-operation would potentially be as affected as it would have been with no deal during the Article 50 negotiations, unless specific measures were agreed or taken unilaterally by the EU.

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