‘Unelected’ prime minister should resign and become the shortest-serving leader in UK history, says opposition leader.

British Labour leader Jeremy Corbyn promised to hold Boris Johnson’s government to account when Parliament returns on Wednesday, again calling for a man he described as “this unelected prime minister” to resign.

The Supreme Court ruled earlier on Tuesday that Johnson‘s decision to suspend Parliament was unlawful, prompting several opposition leaders to demand the prime minister step down.

The stinging judgment by all 11 of the court’s sitting justices undermines Johnson’s already-fragile grip on power and gives legislators more scope to try to stop him taking the UK out of the European Union next month, with or without a divorce deal.

“Tomorrow, Parliament will return. The government will be held to account for what it has done,” said Corbyn.

“Boris Johnson has been found to have misled the country. This unelected prime minister should now resign,” he told his party to thunderous applause and shouts of “Johnson out”.

“That would make him the shortest-serving British prime minister in history and rightly so. His is a born-to-rule government of the entitled who believe that the rules they set for everyone else don’t apply to them.”

‘Strongly disagree’

Johnson was defiant after the historic court ruling saying he had no intention of resigning.

He said on Tuesday while attending the UN General Assembly in New York that he would respect the UK court’s decision but pledged to move on with Brexit despite the ruling.

Johnson – asked about critics’ calls for him to resign for misleading the Queen over the issue – pledged to stay on as prime minister and said he was flying back to London overnight.

“I have to say that I strongly disagree with what the justices have found,” Johnson told reporters in New York. “I don’t think that it’s right but we will go ahead and of course Parliament will come back.”

The Supreme Court ruling said Johnson had not given any reason – “let alone a good reason” – for suspending the legislature for five weeks, an act that had had an “extreme” effect on the fundamentals of British democracy.

Johnson said at the time the suspension – also known as “prorogation” – was necessary to present a new domestic legislative agenda, a ceremonial event that culminates in a speech made by the queen outlining the government’s plans.

The prime minister spoke to Queen Elizabeth after the ruling, a government official said on condition of anonymity. Asked if it had been an apologetic call, the official declined to discuss the content of the conversation.

Not going anywhere?

Standing alongside US President Donald Trump at the UN, Johnson was asked if he would resign.

“No, no, no,” he replied, while Trump interjected: “I’ll tell you, I know him well, he’s not going anywhere.”

John Bercow – the speaker of the House of Commons, the lower and much more powerful chamber – said it would reconvene at 11:30am (10:30 GMT) on Wednesday.

“Tomorrow is another day in Parliament,” Johnson said, although what will ensue there is not clear. He has also not ruled out suspending Parliament again.

Former Conservative Prime Minister John Major, who had joined anti-Brexit campaigners and opposition legislators in the legal challenge against the prorogation, said Johnson should give an “unreserved apology” to Parliament.

“No prime minister must ever treat the monarch or Parliament in this way again,” he said in a statement.

Buckingham Palace declined to comment.