Brexit Day on 31 January 2020 is to be set in stone this Wednesday when the European Parliament casts a final ballot in Brussels copper-fastening the terms of Britain's divorce deal from the EU.
Today's historic legislative act -- the last for the 72 remaining British MEPs who will leave immediately after the ballot -- will allow Brexit to officially take effect on Friday at 2300 GMT, midnight for most of continental Europe and 11:00 pm in Britain.
British Prime Minister Boris Johnson has insisted that date will see Brexit "done". But the European Union has underlined that the next, thornier phase of the split -- working out a treaty to define the future relationship between the two sides -- is about to begin.
Those negotiations are set to go to late this year.
By the end of 2020, a transition period easing Britain out of EU rules and regulations will expire, unless extended by both sides -- something that Johnson has ruled out.
Status quo for 11 months
The transition period, a standstill provision, means ordinary Britons and EU citizens will see little visible change, and indeed London will continue to contribute to the EU budget.
However from this weekend onward, Britain will be excluded from the EU's institutions and decision-making.
It will officially be what the bloc calls a "third country" -- a non-EU state. A close neighbour, and an important trade and security partner, but on the periphery of Europe's single-market, reduced to 27 nations with a combined population of 450 million.
The "withdrawal agreement" being ratified today, protects the rights of EU and British citizens currently residing in each other's territory, Britain's financial obligations, and a customs regime that will keep the UK territory of Northern Ireland largely under European rules.
Britain's Johnson and Queen Elizabeth II and Brussels' most senior officials signed off on the accord last week. Ratification by the European Parliament is a formality, albeit a necessary one under European law.
Keeping a lid on jingoism in post-Brexit Britain
Meanwhile, Prime Minister Johnson, conscious of UK divisions entrenched since the 2016 referendum that ushered in Brexit, is steering clear of a public display of triumphalism.
He recently dismissed pro-Brexiteer proposals to have London's Big Ben temporarily revived from a costly renovative hiatus to symbolically chime in the moment.
Although bolstered by a big parliamentary majority, he faces resentment from British "remainers", a resurgent independence push in anti-Brexit Scotland, and fears among UK businesses about what the loss of frictionless access to the EU's single market will mean for revenues and jobs.
Above all, he has to demonstrate the UK can navigate alone in a world increasingly roiled by geopolitical tussles between the three biggest players -- the US, the EU and China -- that are affecting policies on trade, technology, security guarantees and climate change.
There may be trouble ahead
Neither the United States nor the European Union are likely to offer Britain an easy ride.
Johnson riled Washington on Tuesday by approving plans to use technology from Chinese telecoms giant Huawei in rolling out 5G networks across the UK, despite US warnings that it poses a data security threat.
US Secretary of State Mike Pompeo is visiting London this Wednesday and is expected to hammer home his opposition to the move -- a point that could raise obstacles to an offer to strike a US-UK trade deal.
And Brussels has signalled that it intends to make demands for EU fishermen to operate in British waters a priority in its negotiations with the UK, linking it to London's hopes of securing financial services access to the EU.
EU chief Brexit negotiator, Michel Barnier,recently warned "it is absolutely clear that there will be negative consequences" from Brexit.
Speakin in Belfast on Monday Barnier underlined "whatever agreement we reach on our future relationship, Brexit will always be a matter of damage limitation."