The end of the transition period, four-and-a-half years after a majority in the UK voted to quit the European Union, is a significant moment in the nation's history. After almost five decades as part of the bloc, the UK will now forge a separate path, CNN reported.
UK Prime Minister Boris Johnson said Thursday that Britain will be an "open, generous, outward-looking, internationalist and free trading" country that is "free to do things differently, and if necessary better" than the EU.
"We have our freedom in our hands and it is up to us to make the most of it," Johnson said during his New Year's address, just hours before the end of the transition period.
The divorce has been a painful, drawn-out process. And despite the post-Brexit trade deal agreed by the UK and EU in the closing days of the year, and voted through by British lawmakers on the eve of the December 31 deadline, much uncertainty lies ahead.
Opening the debate on the bill Wednesday, Johnson told members of Parliament that the deal would "open a new chapter" and allow the UK to take "control of our laws and our national destiny."
"This bill, it embodies our vision -- shared with our European neighbors -- of a new relationship between Britain and the EU as sovereign equals, joined by friendship, commerce, history, interests and values, while respecting one another's freedom of action and recognizing that we have nothing to fear if we sometimes choose to do things differently," Johnson said.
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But critics warn that the UK economy will suffer as a result of Brexit, with many businesses unprepared for the changes ahead, particularly coming as the nation staggers under the impact of the coronavirus pandemic.
Now the UK has left the single market and customs union, goods crossing the border will be subject to customs and other checks. Delays and disruption could occur as hauliers discover they lack the correct paperwork, or that new software systems collapse under pressure.
Keir Starmer, leader of the main opposition Labour Party, last week warned that "there are serious questions about the government's preparedness for the new arrangements" after the negotiations went down to the wire.
He told Labour lawmakers to support the bill rather than risk the "devastating" consequences of the UK crashing out of the EU with no trade deal. But Starmer said the "thin agreement" reached by Johnson's government "does not provide adequate protection for British manufacturing, our financial services, creative industries, or workplace rights."
Scotland's First Minister Nicola Sturgeon said in a tweet, sent as the clock struck 11 p.m. UK time, that Scotland will be "back soon, Europe." Scots voted overwhelmingly to remain in the EU in the 2016 referendum and Brexit has injected new energy into the fight for Scottish independence.
The EU-UK trade deal did not cover Gibraltar, the Overseas British Territory that lies on the southern tip of the Iberian peninsula.
Only hours before the transition deadline expired Thursday, Spain and the UK announced that a separate draft agreement had been reached on its post-Brexit status.
'Time to put Brexit behind us'
The UK-EU trade deal has already received provisional approval from the European Union, with both European Commission President Ursula von der Leyen and European Council President Charles Michel formally signing off on the agreement on Wednesday.
"It has been a long road. It's time now to put Brexit behind us," von der Leyen said on Twitter, announcing the move. "Our future is made in Europe."
The European Parliament is expected to examine the deal at a later date before it can be formally ratified by the European Union.
The deal agreed with Brussels sets out a new business and security relationship with the UK's biggest trading partner. It was finally nailed down after months of deadlock over areas such as fishing quotas, how the UK would use state aid to support British businesses post-Brexit, and legal oversight of any deal struck.
The agreement, which preserves Britain's tariff- and quota-free access to the bloc's consumers, spares the UK some of the most dire potential consequences from Brexit as it battles a crippling pandemic.
But while it may have prevented a crippling blow to Britain's ailing economy, the trade agreement will still leave the country poorer at a time when it faces a jobs crisis and the worst recession in more than 300 years.
The deal also appears to mostly cover trade in goods, where the UK has a deficit with its EU neighbors, but excludes key service industries like finance, where it currently enjoys a surplus.
Some UK newspaper front pages sounded a triumphal note Thursday despite the potentially rocky road ahead.
"Britain FINALLY free from the EU" said the Daily Express, while The Times of London declared "It's goodbye to all that as Brexit trade deal signed."
The Daily Mail hailed "two giant leaps to freedom," in a headline referencing both the signing into law of the Brexit trade deal and UK regulators' approval of the Oxford/AstraZeneca coronavirus vaccine a day earlier.
But soaring rates of coronavirus infections may put paid to any Brexit supporters' hopes of celebrating the end of the transition period on Britain's streets.
More than three-quarters of England's population are now under the country's toughest restrictions, aimed at limiting the spread of a new, more contagious coronavirus variant.
News of that variant prompted France, along with other nations in Europe elsewhere, to shut off travel from the UK. As thousands of trucks were stranded at the British port of Dover in the run-up to Christmas, some observers feared it also foreshadowed the potential chaos of a no-deal Brexit.
Meanwhile, the full impact of Brexit on Britons living in the EU, as well as EU citizens living in Britain, remains to be seen. The 3 Million, a grassroots organization of EU citizens in the UK, has highlighted concerns over those who do not realize they must apply to the EU Settlement Scheme by the end of June to protect their UK rights.
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The agreement in principle struck between London and Madrid will avoid a hard border between Gibraltar and Spain, Spanish Foreign Minister Arancha Gonzalez Laya told a televised press conference Thursday.
This was something many local residents, on both sides of the border, had feared as the transition period ends, she said.
Gonzalez Laya said an interim period was expected for six months until a new treaty is finalized. Unlike the rest of the UK, Gibraltar will remain a part of EU agreements, such as the Schengen area, allowing a free flow of people and goods across members' borders.
"Spain will be ultimately responsible for the application of Schengen in Gibraltar," Gonzalez Laya said.
UK Foreign Secretary Dominic Raab said the UK had a "warm and strong relationship with Spain."
"Today, working side by side with the Chief Minister of Gibraltar, and following intensive discussions with the Spanish government, we reached agreement on a political framework to form the basis of a separate treaty between the UK and the EU regarding Gibraltar. We will now send this to the European Commission, in order to initiate negotiations on the formal treaty," he said.
"In the meantime, all sides are committed to mitigating the effects of the end of the transition period on Gibraltar, and in particular ensure border fluidity, which is clearly in the best interests of the people living on both sides."
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