This article originally published in February 2019 has been updated following the UK general election in December.
By law, the United Kingdom is due to leave the European Union at the end of the Article 50 process with or without a divorce agreement, in the absence of an alternative arrangement. After three extensions, the scheduled departure date is now January 31, 2020.
The resounding victory for Boris Johnson's Conservative Party at the December 12 election makes it highly unlikely that the UK will leave the European Union without a divorce agreement in place.
The revised UK-EU deal struck in October 2019 needs the approval of the British parliament – where the ruling Tories' 80-seat majority in the House of Commons should assure safe passage.
It also needs ratification by the European Parliament. Although there have been warnings that citizens' rights safeguards need beefing up, MEPS are thought unlikely to reject the agreement as to do so would risk a damaging "no deal" Brexit.
If, for any reason, the UK leaves the EU without a deal, existing legal arrangements would abruptly cease to apply and many aspects of everyday life would be affected.
If as expected, the UK departs with a ratified divorce deal, the provisions in the Withdrawal Agreement will have the force of an international treaty. These include the financial settlement, citizens' rights – those of EU nationals living in the UK, and Britons on the continent – and arrangements for Northern Ireland.
However, even in the event of a "smooth" Brexit with a divorce agreement in place, another "no deal" scenario could loom in 2020, relating to trade and the future UK-EU relationship.
Preparations for a no-deal scenario have been stepped up – as have warnings of damaging consequences to the economy and for future UK-EU relations. These have often been dismissed as scare stories by some Brexit supporters.
Euronews has examined in detail how the rules would change under no-deal, and how this might affect the UK and the EU. Articles are clickable in the sections below.
This scenario could occur either if the UK leaves the EU without a ratified divorce deal – or if the post-Brexit trade negotiations fail to produce an agreement by the end of the scheduled transition period on December 31, 2020.
Once outside the EU's customs union and single market and in the absence of successfully negotiated alternative, the UK will trade with the EU under World Trade Organisation terms. Our explainer looks at the potential impact of WTO rules and warnings of disruption to the economy on both sides of the English Channel.
In the run-up to the previous Brexit deadlines in March and then October 2019, preparations for a no-deal scenario were stepped up – accompanied by warnings of damaging consequences to the economy and for future UK-EU relations. These have often been dismissed as scare stories by some Brexit supporters.
We examine how EU citizens living in the UK and British nationals on the continent would be affected by a no-deal Brexit.
IMPORTANT: if the UK leaves the EU with a ratified divorce deal, this scenario will become obsolete.
Travel and consumer issues
What no-deal would mean for travellers and consumers, covering issues such as passports and visas, health cover, driving, roaming charges, and cross-border legal cases.
The European Commission’s Contingency Action Plan for Brexit lays out basic plans in a no-deal scenario to regulate citizens’ rights, financial services, air transport, road haulage, customs and exports, and climate policy.
It does not cover issues such as cooperation on security, crime and terrorism. However, a British government paper published when Theresa May was in office makes it clear that the UK would no longer have a formal relationship with Europol, and would no longer be part of existing systems on data-sharing, extradition, and co-operating to fight money-laundering and terrorist financing. The UK's then security minister warned that both sides would be put at greater risk.
In aviation, aerospace companies have warned that the Johnson's government's plans to diverge from EU rules will bring increased cost and complexity. The government says it aims to pursue additional agreements.
For scientific research, the British government has guaranteed funding for UK competitive bids for EU projects submitted before Brexit. But there is uncertainty over future partnerships beyond Horizon 2020, the EU research and innovation programme, when it ends next year. The government says it wants talks with the EU to ensure the UK can continue taking part in programmes as a third country.