"We'll see where we get," Johnson said, referring to planned talks with outgoing European Commission president Jean-Claude Juncker in Luxembourg on Monday.

"I'm cautiously optimistic but whatever happens we will come out [of the EU] on October 31," he said following a speech in northern England on Friday.

He said his government is "working incredibly hard to get a deal".

Irish Prime Minister Leo Varadkar told Ireland's national broadcaster RTE earlier on Friday that "the gap is very wide" between Brussels and London on a possible deal.

Asked whether he trusts Johnson, amid accusations by British opposition MPs that he is merely paying lip service to talks while preparing for a no-deal Brexit, Varadkar said: "I do [trust him]. I believe when he says he wants a deal on Brexit, he is acting in good faith and our teams are in contact and we are exploring what is possible.

"The gap is very wide but we will fight for and work for no no-deal until the last moment, but not at any cost, and at the same time we are preparing the country for no-deal if we end up in that scenario."

Johnson faced more calls on Friday to recall parliament after Scotland's top court ruled that his suspension of the legislature was unlawful.

He was also criticised for failing to comply with a parliamentary order to publish documents detailing how he decided to prorogue, or suspend, parliament and how the government compiled its impact assessment for a possible no-deal Brexit.

Johnson again hinted on Friday that he could ignore a new law designed to delay Brexit and prevent Britain from leaving the EU without a deal.

"I think the people of this country want us to get Brexit done," he said.

"Whatever the shenanigans that may be going on at Westminster (parliament) we will get on with delivering our agenda and preparing to take this country out of the EU on October 31," Johnson said.

He claimed there would be "ample time for parliament to consider the deal" that he hopes to conclude at an October 17-18 EU summit.

The suspension will only deprive MPs of "about four days of parliamentary sitting time", he said.

In a detailed ruling published late Thursday, the Scottish court said it believed Johnson had sought the suspension in a "clandestine" manner.

John Bercow, the Speaker of parliament's elected main house, the Commons, said it was "astonishing" that people were discussing whether the prime minister would obey the law.

"Not obeying the law must surely be a non-starter," Bercow said in a speech on Thursday night, adding that it would be a "terrible example to set to the rest of society".

Johnson said earlier that the legal questions over his suspension of parliament must be decided by Britain's Supreme Court in an appeal hearing expected to open on Tuesday.

Australian Associated Press