UK Prime Minister Boris Johnson has rejected accusations that he lied to the Queen over his controversial suspension of Parliament in the run-up to the Brexit deadline.

Johnson was asked on Thursday if he had lied to the monarch, after a Scottish court ruled the day before that his government's advice to the Queen, which led to the five-week prorogation, was "unlawful."

"Absolutely not," Johnson replied. "The High Court in England plainly agrees with us but the Supreme Court will have to decide."

"We need a Queen's Speech, we need to get on and do all sorts of things at a national level," he added.

Johnson has always insisted that his decision was a routine device that allowed the government to start a new parliamentary session with a fresh legislative agenda. Critics describe it as an audacious move to reduce the amount of time available to the opposition to block a no-deal Brexit.

The Scottish judges disagreed with the government, saying Wednesday that the suspension was motivated by the "improper purpose of stymying Parliament."

UK lawmakers are now not scheduled to return to Parliament until October 14, but Johnson said that MPs would have enough time to debate Brexit before and after the EU summit on October 17 and 18, where Johnson has said he hopes to secure a deal.

"I'm very hopeful that we will get a deal, as I say, at that crucial summit. We're working very hard -- I've been around the European capitals talking to our friends," he said.

"I think we can see the rough area of a landing space, of how you can do it -- it will be tough, it will be hard, but I think we can get there."