was despite the Labour government promising in 2004 to hold a referendum on the previously proposed Constitution for Europe. On 23 June 2016, the United Kingdom voted to leave the European Union in a referendum. After the referendum, it was debated as to how and when the UK should leave the EU. On 11 July 2016, the Cabinet Office Minister, John Penrose failed to deliver a final answer on whether it would be at the disposal of the Prime Minister and one of the Secretaries of State, through the royal prerogative, or of Parliament, through primary legislation. In October 2016 the Conservative Prime Minister, Theresa May, announced that Article 50 would be invoked by "the first quarter of 2017". On 24 January 2017 the Supreme Court ruled in the Miller case by a majority that the process could not be initiated without an authorising act of parliament, but unanimously ruled against the Scottish government's claim in respect of devolution that they had a direct say in the decision to trigger Article 50. Consequently, the European Union (Notification of Withdrawal) Act 2017 empowering the prime minister to invoke Article 50 was passed and enacted by royal assent in March 2017. Invocation of Article 50 by the United Kingdom government occurred on 29 March 2017, when Sir Tim Barrow, the Permanent Representative of the United Kingdom to the European Union, formally delivered by hand a letter signed by Prime Minister Theresa May to Donald Tusk, the President of the European Council in Brussels. The letter also contained the United Kingdom's intention to withdraw from the European Atomic Energy Community (EAEC or Euratom). This means that the UK will cease to be a member of the EU on 30 March 2019, unless an extension to negotiations is agreed upon by the UK and EU. The leaving date was subsequently revised by agreement with the EU to be 31 October 2019. This led to a change of prime minister who promised to leave the EU on this date either with a revised deal or with no-deal. The UK withdrew from the EU at 23.00 GMT on 31 January 2020, beginning a transition period that was set to end on 31 December 2020. During the 11-month transition period, the UK and EU negotiated their future relationship which resulted in the EU–UK Trade and Cooperation Agreement which was agreed on 24 December 2020 just days before