The highest court in the U.K. ruled Tuesday that Prime Minister Boris Johnson's decision to suspend Parliament for five weeks was unlawful.

Johnson, who has been pushing for Britain's withdrawal from the European Union, suspended Parliament on Sept. 10 through Oct. 14, leaving opponents little time to act before the Oct. 31 Brexit deadline.

Responding to the ruling, Johnson told the BBC the verdict was not right but would be respected. He also said that the government would "get on and deliver Brexit on October 31st come what may." There is currently no Brexit deal in place although lawmakers have already voted to prevent Johnson's government from taking the U.K. out of the bloc without a deal.

Sterling jumped nearly 0.40% after the decision to trade at $1.2478.

The president of the Supreme Court, Brenda Hale, said Johnson's attempt was not a normal suspension and that it had taken place in exceptional circumstances. She said no justification for the government taking such extreme action — to suspend Parliament for five weeks — had been put forward.

Hale said that the decision by Johnson's government to advise the queen to suspend parliament was unlawful "because it had the effect of frustrating or preventing the ability of Parliament to carry out its constitutional functions without reasonable justification."

Hale said the judges' decision was unanimous.

Although the judges ruled that the suspension is void, it was to lawmakers to decide what to do next. The court said Johnson's lawyer had told the court that the prime minister would comply with the judgment.

John Bercow, the speaker of the House of Commons, welcomed the decision and said Parliament must convene without delay, Reuters reported. Parliament is now expected to reconvene on Wednesday.