Thehe UK Supreme court ruled unanimously Wednesday that it will be forced to defer to the European Court of Justice (ECJ) in cases involving EU law until Brexit is fully completed, placing the courts under EU jurisdiction.

This ruling comes from a case involving input VAT deductions for supplies purchased in connection with the vitamin and mineral business Zipvit. The court acknowledged that the case raised four questions previously unresolved in the case law, concluding that UK courts are obliged to refer such questions to the ECJ during the Brexit transition.

Martin Howe, QC, chairman of Lawyers for Britain stated that this decision resulted from a “highly flawed” withdrawal agreement that prevents full sovereignty for the UK. Although the implementation period for Brexit is set to end on December 31, 2020, Howe has urged the UK to modify the agreement before then.