UK's Boris Johnson defiant after court ruling, challenging opposition MPs to call confidence vote in his government
Britain's Prime Minister Boris Johnson says he wants to leave the EU on October 31 with or without a deal PRU/AFP

British Prime Minister Boris Johnson on Wednesday challenged opposition MPs to call a confidence vote in his government, in a defiant response to the Supreme Court decision to strike down his suspension of parliament.

Britain's highest court on Tuesday found the Conservative leader acted illegally in suspending, or proroguing, parliament for five weeks in the run-up to Brexit.

But Johnson showed no contrition as he faced the newly reconvened House of Commons, and repeated his determination to leave the European Union on October 31 with or without a deal with Brussels.

To huge cheers from his Conservative MPs, he condemned the court ruling as "wrong".

Faced with calls to resign, he instead challenged Labour and other opposition parties to call a confidence vote in his government, saying he would make time for a vote on Thursday.

"Will they have the courage to act or will they refuse to take responsibility and do nothing but dither and delay... what are they scared of?" he said.

AFP / Gal ROMA Key Brexit dates

Labour leader Jeremy Corbyn called on Johnson to resign, saying: "he is not fit for the office that he holds".

But he said he would not back an election until the prime minister's threat of leaving the EU without a divorce deal was removed.

In the week before parliament was suspended earlier this month, MPs passed a law requiring Johnson ask the EU to delay Brexit if he cannot get a deal.

"If he wants an election, get an extension and let's have an election," Corbyn said.

Meanwhile a Conservative source said the government would seek Thursday to suspend parliament for three days next week for the centre-right party's annual conference.

It is standard practice to have a recess while all the parties hold their gatherings in September, but MPs are so angry they could vote against the plan.

- 'Paralyzed parliament' -

Johnson, who only took office in July, says he suspended parliament for five weeks until October 14 to launch a fresh legislative program.

But critics accused him of trying to silence MPs at a crucial time, with the terms of Brexit still undecided three years after the 2016 EU referendum.

On Tuesday, 11 Supreme Court judges unanimously ruled that Johnson's decision to advice Queen Elizabeth II to suspend parliament was unlawful.

AFP / ISABEL INFANTES Johnson returned from a trip to the UN in New York to a political storm in Britain

They said the effect had been to frustrate parliament, and declared the suspension void.

But Johnson, who flew back early from the UN General Assembly in New York to address MPs, hit back by accusing lawmakers of trying to frustrate Brexit.

Parliament was "gridlocked, paralyzed and refusing to deliver on the priorities of the people", he said.

"This parliament must either stand aside and let this government get Brexit done or bring a vote of confidence and finally face the day of reckoning with the voters," he added.

Johnson's spokesman said that a failure to call a confidence vote this week would be seen as a mandate to proceed with his Brexit strategy.

The premier has already tried twice to call an early election, hoping to take advantage of opinion polls showing voters like his tough Brexit stance.

However, a snap election requires support of two-thirds of MPs, and Johnson does not have even a simple majority in the 650-seat House of Commons.

"We cannot trust this prime minister, his time must be up. His days of lying, of cheating and of undermining the rule of law," Scottish National Party (SNP) Westminster leader Ian Blackford said.

"He should resign but if he fails to do so, yes the opposition must unite to trigger a vote of no confidence to bring this chaotic government down."

- EU negotiations -

AFP / Tolga AKMEN Pro- and anti-Brexit campaigners demonstrated outside parliament as it reconvened

The Supreme Court ruling comes after a series of defeats in parliament for Johnson, the most damaging of which was the law designed to avoid a "no deal" Brexit.

Johnson continues to insist he will leave the EU on October 31, but unless he finds a loophole in the law, he can only do this by getting a deal.

He is seeking to amend the terms struck by his predecessor Theresa May, which were rejected by MPs three times -- and insists he is making progress.

He suggested Wednesday that an alternative to the hated "backstop" plan for the Northern Irish border was taking shape which would not trap Britain in the EU's customs union indefinitely.

However, EU leaders are not as optimistic.