In yet another setback for the British Prime Minister Boris Johnson, Scotland’s highest court of appeal ruled on Wednesday that his decision to suspend parliament for five weeks is illegal and should be annulled.

British Parliament was suspended – on Monday until Oct. 14, a move the PM’s opponent argued was designed to thwart their attempts to scrutinize his plans for leaving the European Union and allow him to push through a no-deal Brexit on Oct. 31.

“You cannot break the law with impunity, Boris Johnson,” said Joanna Cherry, the Scottish National Party lawmaker who led the challenge. “We are calling for parliament to be recalled immediately.” she told Sky News after the unanimous verdict by three judges at Scotland’s Court of Session.

Johnson’s office said the government would appeal to the Supreme Court, the highest judicial body in the United Kingdom. It was not immediately clear what effect the ruling would have.

“Any decision to accelerate the meeting of Parliament during prorogation is a matter for the government.” a spokeswoman for the Speaker of the House of Commons told the BBC.

Johnson announced on Aug. 28 that parliament would be prorogued, saying the government wanted the suspension so it could then launch a new legislative agenda.

Opponents said the real reason was to shut down debate and challenges to his Brexit plans. The court was shown documents that showed Johnson was considering prorogation weeks before he formally asked Queen Elizabeth to suspend the legislature.

“The UK government needs to bring forward a strong domestic legislative agenda,” a government spokesman said in response to Wednesday’s ruling. “Proroguing parliament is the legal and necessary way of delivering this.”

However, in an excoriating judgment, the Scottish judges ruled the principal reason for suspension was to stymie lawmakers and allow Johnson to pursue a no-deal Brexit policy.

“This was an egregious case of a clear failure to comply with generally accepted standards of behavior of public authorities.” concluded one judge, Philip Brodie, according to a summary of the court verdict.

Judge James Drummond Young had determined that “the only inference that could be drawn was that the UK government and the Prime Minister wished to restrict Parliament.” the summary said.