UK Government Triggers Article 50

March 29, 2017

  1. The UK government has today triggered Article 50 – the official legal notification to the EU that the UK is going to leave the bloc[1].  This means that, unless otherwise agreed with the EU member states, the UK will be out of the EU by end March 2019.
  2. The Supreme Court ruled in January 2017 that the UK government could not invoke Article 50 without first obtaining the approval of Parliament.  The European Union (Notification of Withdrawal) Act 2017 has now been approved by Parliament and received Royal Assent on 16 March 2017.  This Act is now law, and it authorises the Prime Minister to give notice under Article 50.
  3. The UK now has two years to negotiate the terms of its new relationship with the EU.  This incredibly complex process will involve unpicking 43 years of political, economic, legal  and regulatory integration with the EU.
  4. A broad outline of the Brexit deal being sought by the UK government was given in a White Paper on 2 February 2017[2].  However the White Paper sets out only very high level aims and is light on any detail.  The White Paper states that the UK will not  stay in the EU’s single market as it would mean the UK staying under the auspices of the Court of Justice of the European Union and having to allow unlimited EU immigration. But the UK will instead pursue an ambitious and comprehensive free trade agreement and a new customs agreement.
  5. The UK Parliament will have to ratify the eventual withdrawal agreement.  On the EU-side, the final agreement must be agreed by the Council of the European Union (through a so-called qualified majority vote, being 72% of EU member states representing at least 65% of the EU population) and the European Parliament.  In addition, if the final draft is considered a "mixed agreement" that covers issues over which both the EU and a member state have responsibility (e.g., security or foreign policy issues), the agreement will need to be ratified by the parliament of every member state; this means every EU country would have a veto. 
  6. If no deal is reached within the two-year period, the negotiating period can be extended by unanimous agreement of the European Council.  The UK will otherwise leave the EU with no withdrawal agreement in place.
  7. A legal challenge has begun in the High Court in Dublin to determine whether Article 50 can be withdrawn once invoked.  Tax barrister Jolyon Maugham and others are hoping the Irish courts will make a referral to the Court of Justice of the European Union on the issue.  If the CJEU were to rule that Article 50 is revocable, it would enable the UK to reject the outcome of Brexit negotiations should they not prove acceptable to the UK Parliament or voters, and remain in the EU. 
  8. Scotland’s First Minister Nicola Sturgeon has said that it is "democratically unacceptable" that Scotland faces being taken out of the EU when a majority of voters in Scotland wanted to remain.  The Scottish Parliament has voted this week to back Nicola Sturgeon’s call for a second referendum on independence from the United Kingdom (her SNP government won the vote with the support of the Scottish Greens, despite opposition from the Conservatives, Labour and Liberal Democrats).  Nicola Sturgeon will now ask for permission from the UK Parliament to hold a second referendum on Scottish independence between the autumn of 2018 and the spring of the following year.  That would coincide with the expected conclusion of the Brexit negotiations.  The UK government has already said it will block a vote within two years (saying "now is not the time"), but may leave the doors open for a vote after the Brexit deal is done.  There is some suggestion that Nicola Sturgeon accepts this position, albeit not publicly. 
  9. Sinn Fein (the second largest party in the Northern Irish Assembly) has called for a referendum on Northern Ireland leaving the UK and joining the Republic of Ireland.  In Wales, Plaid Cymru (the third largest party in the Welsh Assembly, after Labour and Conservatives) has stated that "all options should be on the table" following Brexit.

In brief – key players for Brexit negotiations


Theresa May, UK Prime Minister

David Davis, Secretary of State for Exiting the European Union

Liam Fox, Secretary of State for International Trade

Boris Johnson, Secretary of State for Foreign and Commonwealth Affairs

UK Civil Service, including Department for Exiting the EU and Department for International Trade


The European Council (comprising heads of the 28 member states together with its President Donald Tusk and the President of the European Commission Jean-Claude Juncker) defines the EU’s overall direction and priorities. 

The Council of the European Union (made up of ministers from member states) negotiates and adopts legislation and concludes international agreements.  Didier Seeuws, a Belgian diplomat, has been appointed by the Council to lead its taskforce on Brexit.

The European Commission (the EU’s "civil service") supports the Council in undertaking negotiations.  Michel Barnier, former Vice-President of the European Commission and former French Europe Minister, has been appointed by the Commission as its European Chief Negotiator for Brexit.

The European Parliament (comprising elected MEPs from each member state) scrutinises, amends and adopts legislation and international agreements.  The European Parliament has elected Guy Verhofstadt, a former Belgian Prime Minister and MEP, to act as its representative during negotiations.

Subject to French (7 May 2017) and German (24 September 2017) elections this year, the French President and German Chancellor are expected to play key roles in the negotiations.



This client alert was prepared by London partners Stephen Gillespie, Charlie Geffen and Nicholas Aleksander and of counsel Anne MacPherson.  We have a working group in London (led by Stephen Gillespie, Nicholas Aleksander, Patrick Doris, Charlie Geffen, Ali Nikpay and Selina Sagayam) that has been considering these issues for many months.  Please feel free to contact any member of the working group or any of the other lawyers mentioned below.

Ali Nikpay – Antitrust
[email protected]
Tel: 020 7071 4273

Charlie Geffen – Corporate
[email protected]
Tel: 020 7071 4225

Stephen Gillespie – Finance
[email protected]
Tel: 020 7071 4230

Philip Rocher – Litigation
[email protected]
Tel: 020 7071 4202

Jeffrey M. Trinklein – Tax
[email protected]
Tel: 020 7071 4224

Nicholas Aleksander – Tax
[email protected]
Tel: 020 7071 4232

Alan Samson – Real Estate
[email protected]
Tel:  020 7071 4222

Patrick Doris – Litigation; Data Protection
[email protected]
Tel:  020 7071 4276

Penny Madden QC – Arbitration
[email protected]
Tel:  020 7071 4226

James A. Cox – Employment; Data Protection
[email protected]
Tel: 020 7071 4250  

Gregory A. Campbell – Restructuring
[email protected]
Tel:  020 7071 4236

Selina Sagayam – Corporate [email protected]
Tel:  020 7071 4263

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