European lawmakers have approved the final ratification of the post-Brexit trade deal between the European Union and the United Kingdom, nearly five years after Britain decided to leave the bloc.

The deal, which was finalized on Christmas Eve, had already been ratified by the U.K. Parliament and conditionally came into force pending the European Parliament's approval, which marks the final legal hurdle.

Lawmakers at the European Parliament endorsed the free trade agreement by 660 votes in favor, 5 against, and 32 abstentions. The vote took place Tuesday but results were not announced until Wednesday morning.

The U.K. Had joined the the bloc in 1973.

In a debate ahead of the vote, many legislators rued Britain's departure but insisted ratifying the text was the best option to avoid economic disruptions and ensure the EU's single market integrity.

Amid ongoing tensions between London and Brussels over Northern Ireland trade rules, the EU Parliament also said that the agreement will provide extra legal tools to “prevent and protect against unilateral divergence from the obligations to which both parties signed up.”

Earlier this year, the European Union accused Britain of breaching international law after the U.K. Government unilaterally extended until October a grace period for not conducting checks on goods moving between Northern Ireland and the rest of the U.K. The move led the EU to start legal action against its former member nation.

Northern Ireland is part of the U.K. But remained part of the EU's single market for goods after Brexit to avoid customs checks at the territory's border with EU member Ireland. An open Irish border helped underpin the peace process that ended decades of sectarian violence in Northern Ireland.

But tensions and violence have escalated in recent weeks, with unionists saying the arrangement the British government and the EU worked out has amounted to the creation of a border between the territory and the rest of the U.K.

The sensitivity of Northern Ireland's status also was seen in September when the U.K. Parliament considered legislation that would have given Prime Minister Boris Johnson's government the power to override part of the Brexit withdrawal agreement relating to Northern Ireland.

The tension increased in January when the EU threatened to ban shipments of coronavirus vaccines to Northern Ireland as part of moves to shore up the bloc's supply. That would have drawn a hard border on the island of Ireland — exactly the scenario the Brexit deal was crafted to avoid.

Relations between the EU and the U.K. Have been strained since a Brexit transition period ended on Jan. 1. The two sides have argued so far this year over issues ranging from COVID-19 vaccine supplies to the full diplomatic recognition of the EU in Britain.