The UK and European Union will Wednesday sign a mammoth trade pact to put the seal on their drawn-out Brexit divorce in the dwindling hours before they part ways definitively at the dawning of 2021.

EU chiefs Ursula von der Leyen and Charles Michel will ink the 1,246-page Trade and Cooperation Agreement at 0830 GMT, officials in Brussels said, days after it was clinched on Christmas Eve following months of hard-fought talks.

The hefty document will then be flown by the Royal Air Force to London for Prime Minister Boris Johnson to add his signature, as the UK parliament embarks on a rushed debate to clear the decks before a December 31 deadline.

According to Downing Street, Johnson will tell MPs that the agreement heralds "a new relationship between Britain and the EU as sovereign equals, joined by friendship, commerce, history, interests and values".

The government only released the accompanying UK legislation on Tuesday afternoon -- less than 24 hours before the debate is to start in parliament an hour after the signing in Brussels.

The government intends to ram all stages of the 85-page European Union (Future Relationship) Bill through the Commons and the House of Lords in one day, before the EU trade deal takes effect at 11:00 pm (2300 GMT) on Thursday.

At that hour -- midnight in Brussels -- the UK will be entirely out of the EU, following an 11-month transition period in place since Brexit took legal effect and more than four years after Britons voted to leave in a divisive referendum.

Each side will work "hand-in-glove whenever our values and interests coincide, while fulfilling the sovereign wish of the British people to live under their own laws, made by their own elected parliament", Johnson will say.

The agreement averted the prospect of a cliff-edge separation which would have seen quotas and tariffs slapped on all cross-Channel trade, exacerbating strains in the middle of the coronavirus pandemic, which has hit Britain harder than most.

British fishermen accused the government of selling them out.

Boris Johnson
Britain's Prime Minister Boris Johnson, seen here campaigning in 2019, will finally 'Get Brexit Done' this week Photo: POOL / Ben STANSALL

Services, accounting for 80 percent of the UK economy, were largely omitted, and the City of London faces an anxious wait to learn on what basis it can continue dealing with Europe in future.

But a faction of arch-Brexiteers in Johnson's ruling Conservatives gave their blessing to the EU agreement on Tuesday, and the main opposition Labour party signalled its reluctant backing, ensuring the legislation will pass.

Despite misgivings among some of his own MPs, who plan to abstain in Wednesday's vote, Labour leader Keir Starmer said neutrality was not an option given the stakes for Britain as it unwinds nearly five decades of integration with the European mainland.

"But the consequences of it are yours, and yours alone," he said, addressing Johnson's government. "We will hold you to account for it, every second you are in power."

Indeed, the full consequences of the agreement will only play out in the coming months, and UK businesses will still be grappling with the kind of customs red tape they have avoided for decades in trading across the Channel.

From January 1, there will no longer be free movement of people from Britain to the EU or vice versa.

The UK government is pulling out of a European student exchange programme that has benefited tens of thousands of young people over the years.

Under the EU deal, musicians are not covered by exemptions allowing for free passage of short-term business visitors, sparking warnings that continental tours by UK bands will become unviable.

The many British owners of European holiday homes are finding that unless they apply for residency permits, they will face limits on how often they can visit their properties.

And they will face new bureaucracy if they want to take their pets.

Under the compressed legislative calendar, the European Parliament will only debate the Brexit deal after the New Year.

Pending that, EU member states gave their green light on Monday for the accord to take provisional effect before Thursday's deadline.

Copyright AFP. All rights reserved.