BRUSSELS — Just a week before the deadline, Britain and the European Union struck a free-trade deal Thursday that should avert economic chaos on New Year’s and bring a measure of certainty for businesses after years of Brexit turmoil.

Once ratified by both sides, the agreement will ensure Britain and the 27-nation bloc can continue to trade in goods without tariffs or quotas after the U.K. breaks fully free of the EU on Jan. 1.

Relief was palpable all around that nine months of tense and often testy negotiations had finally produced a positive result.

The Christmas Eve breakthrough was doubly welcome amid a coronavirus pandemic that has left some 70,000 people in Britain dead and led the country’s neighbors to shut its borders to the U.K. over a new and seemingly more contagious variant of the virus spreading in England.

“We have taken back control of our laws and our destiny,” declared British Prime Minister Boris Johnson, who posted a picture of himself on social media, beaming with thumbs up.

European Commission President Ursula von der Leyen said “it was a long and winding road but we have got a good deal to show for it.”

“It is fair, it is a balanced deal, and it is the right and responsible thing to do for both sides,” she said in Brussels.

The 27 EU countries and the British and European parliaments still need to vote on the agreement, though action by the European body may not happen until after the Jan. 1 breakup. Britain’s Parliament is set to vote Dec. 30.

France, long seen as Britain’s toughest obstacle to a deal, said the uncanny steadfastness among the 27 nations with widely varying interests was a triumph in itself.

“European unity and firmness paid off,” French President Emmanuel Macron said in a statement.