The conclusion of difficult negotiations
The United Kingdom voted to leave the European Union on 23rd June 2016 via a referendum proposed by Prime Minister David Cameron. Article 50 TEU – the exit clause – was triggered for the first time in history by a Member State asking for withdrawal from the European Union.
The Exit Clause
Article 50 TEU sets out the exclusive legal procedure for a Member State to leave the Union. The only condition for withdrawal set in the Treaty is that the withdrawal shall be taken in accordance with the State’s constitutional requirements. In the context of Brexit, the UK Supreme Court established that this could not mean a simple notification from the Government alone, but an Act of Parliament was necessary. As a result of article 50 TEU, rights and obligations resulting from the Treaties ceased to apply. The notification from the United Kingdom triggered two years count-down in accordance with article 50(3) TEU. The leaving Member State and the EU had two years to negotiate an agreement establishing future relationships, nonetheless the European Council could decide unanimously to extend the deadline. During the Brexit period there have been three different extensions.
The EU-UK Withdrawal Agreement
On the 17th October 2019 the United Kingdom and the European Union agreed on the withdrawal agreement, which came into force on the 1st February 2020. The agreement set out the rules of the transition period that would be concluded on the 31st December 2020. It was divided into six parts and it included three different protocols: on Ireland and Northern Ireland, related to the sovereign base areas of the United Kingdom of Great Britain and Northern Ireland in Cyprus, and on Gibraltar.
The UK-EU Trade and Cooperation Agreement
Finally the parties concluded a Trade and Cooperation agreement on the 24th December 2020, after intense negotiations. The UK and the EU will form two distinct regulatory and legal spaces from the 1st January 2021. The agreement is formed by three main pillars: 1) a free trade agreement, 2) a new partnership for our citizens’ security, and 3) a horizontal agreement on governance.
According to the new agreement, the UK will no longer benefit from free movement of goods, persons, capital and services. For example, a visa will now be required for staying for more than 90 days, and there will not be easy recognition of professional qualification. However, concerning the trade of goods, the parties managed to agree on imposing zero tariffs and quotas on goods traded that comply with appropriate rules of origin. Moreover, under the first pillar, the parties stipulated common high standards in order to maintain a level playing field between the two markets e.g. for open and fair competition and sustainable development.
Additionally, the first pillar provides for new types of cooperation between the EU and UK in diverse fields. Since the UK left the single energy market, the EU’s Emissions Trading scheme, and the Euratom, a new energy agreement is now in place. The UK does not participate anymore to the EU aviation market, to the EU single market for transport services, and to the Common Fisheries Policies. New arrangements are now available under the Trade and Cooperation agreement.
Furthermore, under the second pillar – new partnership for citizens’ security – the EU and the UK have set up a new framework for law enforcement and judicial cooperation both in criminal matters. In this scenario, the UK is treated as a third country, thus the cooperation will not be the same level of before. Lastly, under the third pillar, the parties have agreed on creating a Joint Partnership Council to oversee the well-functioning of the agreement, and a dispute settlement mechanism is laid down.
Big changes characterise the Trade and Cooperation agreement between the EU and the UK, for this reason the Commission has published a checklist that should permit the reader to form a more precise idea of the overall transition. The UK is now free to set up its own trading rules and negotiations with countries outside the EU. In the world of UK Prime Minister Boris Johnson: “… the agreement provides for the UK to take back control of our laws, affording no role for EU law and no jurisdiction for the European Court of Justice. The only laws we will have to obey are the ones made by the Parliament we elect.” On the one hand, the EU-UK Trade and Cooperation agreement tried to safeguard certain rights and the integrity of the internal market; on the other hand, it has been stressed in the Commission’s press release that “… by no means, the agreement matches the significant advantages that the UK enjoyed as a Member State”.
Image EU-UK Relations: big changes compared to benefits of EU membership-checklist.
EU Referendum UK votes to leave the EU: BBC Votes Results, (BBC News) available at: https://www.bbc.co.uk/news/politics/eu_referendum/results last accessed 29th January 2021.
 C-C Cîrling, ‘Article 50(1) TEU in practice: how the EU has applied the ‘exit’ clause’  EPRS European Parliamentary Research Service, p. 7.
 UKSC5, R (on the application of Miller and another) v Secretary of State for exiting the European Union  available at https://www.supremecourt.uk/cases/uksc-2016-0196.html last accessed 29th January 2021.
 Article 50(3) Treaty of the European Union (TEU).
 The notification took form of a letter from the UK Prime Minister Theresa May on 29th March 2017, see supra (n.2) p. 8.
 Supra (n.4).
 European Council Decision (EU) 2019/476 taken in agreement with the United Kingdom of 22nd March 2019 extending the period under article 50(3) TEU, OJ L 80I, 22.03.2019. European Council Decision (EU) 2019/584 taken in agreement with the United Kingdom of 11th April 2019 extending the period under article 50(3) TEU, OJ L 101, 11.04.2019. European Council Decision (EU) 2019/1810 taken in agreement with the United Kingdom of 29th October 2019 extending the period under article 50(3) TEU, OJ L 278I, 30.10.2019.
 Council Agreement on the withdrawal of the United Kingdom of Great Britain and Northern Ireland from the European Union and the European Atomic Energy Community, OJ C 384 I/1, 12.11.2019, (“The Withdrawal Agreement”).
 Ibid Article 126. Extension of the transition period was possible as provided by Article 132(1).
 Protocol on Ireland and Northern Ireland, Protocol related to the sovereign base areas of the United Kingdom of Great Britain and Northern Ireland in Cyprus, Protocol on Gibraltar in supra (n.8) respectively p. 92, p. 136, and p. 143.
 The EU-UK Trade and Cooperation agreement (European Commission: press release) [31st December 2020] available at https://ec.europa.eu/info/relations-united-kingdom/eu-uk-trade-and-cooperation-agreement_en last accessed 29th January 2021.
 EU-UK Relations: A new relationship, with big changes (European Commission: press release) [24th December 2020] available at: https://ec.europa.eu/info/publications/eu-uk-trade-and-cooperation-agreement-new-relationship-big-changes-brochure_en last accessed 30th January 2020.
 Trade and cooperation agreement between the European Union and the European Atomic Energy Community, of the one part, and the United Kingdom of Great Britain and Northern Ireland, of the other part, OJ L 444/14, 31.12.2020, (“EU-UK Trade and Cooperation Agreement”), Part II, Heading I, Title VIII.
 Supra (n.13).
 Supra (n.14) Part II, Heading II: Aviation – Part II, Heading III: Road Transport – Part II, Heading V: Fisheries.
 Ibid Part III: Law Enforcement and Judicial Cooperation in Criminal Matters – Part IV: Thematic Cooperation.
 The UK does not participate anymore at Europol and Eurojust. However, they still cooperate, see supra (n.14) Part III, Title V: Cooperation with Europol and Title VI: Cooperation with Eurojust.
 Supra (n.14) Part I, Title II: Institutional Framework and Article 1: Partnership Council.
 Ibid Part VI, Title I: Dispute Settlement.
 EU-UK Relations: big changes compared to benefits of EU membership-checklist, see supra (n.11).
 The UK-EU Trade Cooperation Agreement Summary (UK Government website) [24th December 2020] available at:https://www.gov.uk/government/publications/agreements-reached-between-the-united-kingdom-of-great-britain-and-northern-ireland-and-the-european-union last accessed 30th January 2021, p. 5.
EU-UK Trade and Cooperation Agreement: protecting European interests, ensuring fair competition, and continued cooperation in areas of mutual interests (European Commission: press release) [24th December 2020] available at: https://ec.europa.eu/commission/presscorner/detail/en/ip_20_2531last accessed 29th January 2021.
 Image EU-UK Relations: big changes compared to benefits of EU membership-checklist, see supra (n.11).