parties supporting both "Remain" (Britain Stronger in Europe)and "Leave" (Vote Leave) focused on concerns regarding trade and the European Single Market, security, migration and sovereignty. The result of the referendum was in favour of the country leaving the EU with 51.9% of voters wanting to leave. David Cameron resigned from Parliament on 13 July, which led to Theresa May succeeding him as Prime Minister. The UK remained a member of the EU for the time being, but invoked Article 50 of the Lisbon Treaty on 29 March 2017. This started negotiations on a withdrawal agreement that will last no more than two years (unless the Council and the UK agree to extend the negotiation period), before an exit from the European Union (Brexit) intended on 29 March 2019 but later extended to currently 31 October 2019. The longer-term implications of the referendum vote remain uncertain, with politicians and commentators suggesting various outcomes. The debate on Brexit grew heated. During the 2016 campaign on the referendum, Boris Johnson became a leading proponent of Vote Leave, stating, "The EU is, I'm afraid a job-destroying engine. You can see it all across southern Europe, you can see it, alas, in our country". A victory for Brexit, he argued, would be "independence day" for Britain if it leaves the European Union. By 2019, Johnson was Prime Minister and pushed hard for an exit on 31 October 2019. The opponents warned of bedlam. Political commentator Jonathan Freedland argued in late summer 2019 that the Britain of 2019 is, "in the grip of a populism that is trampling on the norms and constraints of liberal democracy, that is contemplating a collective act of self-harm without precedent, that is bracing itself for disruption, shortages, even civil unrest unknown in peacetime. This is not the consequence of unavoidable war or an unforeseen natural disaster, but is entirely of the country's own making." COVID-19 pandemic Though later reporting indicated that there may have been some cases dating from late 2019, COVID-19 was confirmed to be spreading in the UK by the end of January 2020 with the first confirmed deaths in March. The country was initially relatively slow in implementing restrictions. Subsequent epidemiological analysis showed that over 1000 lineages of SARS-CoV-2 entered the UK in early 2020 from international travellers, mostly from outbreaks elsewhere in Europe, leading to numerous clusters that overwhelmed contact tracing efforts. A legally enforced Stay