Opposition MPs are demanding Parliament be recalled after a court ruling deemed its closure unlawful.
Parliament was suspended – or prorogued – on Monday – something Boris Johnson said was normal ahead of a Queen’s Speech, laying out his policy agenda.
But critics claimed his intention was to avoid scrutiny in the run-up to the Brexit deadline on 31 October.
Shadow Brexit secretary Sir Keir Starmer said Parliament should be recalled as early as this afternoon.
He told the BBC: “Most people didn’t believe Boris Johnson, but for the courts to find he has unlawfully shut down Parliament and that his motive wasn’t the one he said it was? That’s very powerful.
“I call on him to recall Parliament. Let’s get it back open, and sitting this afternoon and tomorrow, so we can debate what happens next and we can debate this judgement.”
The government said it would appeal the decision in the UK’s Supreme Court next week.
But the SNP’s Joanna Cherry, who was one of the lawyers involved with the case in Scotland, said Parliament should be recalled “for the time being”.
She told the BBC that, even if the Supreme Court were to issue its decision immediately, “we will have lost about 10 days of Parliamentary time… so we in the SNP are calling for Parliament to be resumed”.
“We think Parliament should go back and get on with the job of scrutinising this government, looking at what they’re up to.”