LONDON (Reuters) - Britain's Supreme Court is to rule on Wednesday on a challenge to the validity of the controversial Northern Ireland Protocol which governs post-Brexit trade between the region and the rest of the United Kingdom.
The challenge, taken by Brexit activists and the leaders of Northern Ireland's largest pro-British parties, was rejected by Belfast's High Court in 2021 and by the Court of Appeal last year.
The protocol, designed to protect the European Union's single market without creating a land border on the island of Ireland, has caused disruption to trade between Northern Ireland and the rest of the United Kingdom since it came into force at the start of 2021.
The perception that the protocol, which effectively left Northern Ireland in the bloc's trading orbit, undermines the region's place in the United Kingdom has sparked anger in pro-British communities.
The High Court in 2021 rejected all five main arguments made by the parties based on both British and European Union law, saying none justified the judicial review of the protocol requested.
The ruling said that Britain's EU Withdrawal Agreement, which contains the protocol, overrode earlier precedents including parts of the 1800 Act of Union due to the sovereignty of the British parliament and the agreement's status as constitutional legislation.
The challenge was brought by former Democratic Unionist Party leader Arlene Foster, Traditional Unionist Voice leader Jim Allister and former Ulster Unionist Party leader David Trimble among others.