THE European Union's Brexit co-ordinator has hit out at Brexiteers in the wake of the Supreme Court's ruling on Boris Johnson's prorogation.

Guy Verhofstadt was responding to the news that the Prime Minister's decision to suspend the UK Parliament had been ruled unlawful.

The MEP welcomed the finding of the court, and took aim at Johnson and his Brexiteers.

He tweeted: "At least one big relief in the Brexit saga: the rule of law in the UK is alive & kicking. Parliaments should never be silenced in a real democracy. I never want to hear Boris Johnson or any other Brexiteer say again that the European Union is undemocratic."

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The Supreme Court's decision was unanimous, with all 11 justices ruling the prorogation null and void.

Verhofstadt had earlier suggested Johnson's actions had echoes of the Soviet Union.

He tweeted last week: "The British Parliament may be shut down, the @Europarl_EN is not! So next time the Eurosceptics here want to make a ridiculous comparison with the Soviet Union, from now on they can point their finger to Westminster, instead of Strasbourg or Brussels. #EPlenary"

Johnson has vowed to press on with his plans for Brexit despite the ruling.

The Prime Minister said he would abide by the finding of the Supreme Court that the five-week prorogation was "void and of no effect" – even though he disagreed with its conclusion.

Following the legal bombshell, Commons Speaker John Bercow announced that MPs would return to Westminster on Wednesday with the House sitting at 11.30am.

The ruling prompted immediate demands from opposition for Johnson to quit amid claims his position had become untenable.

Downing Street insisted there was no question of Johnson – who was in New York for the UN General Assembly when the result was announced – stepping aside.

A No 10 source said: "The PM will not resign following the judgment."

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While the Prime Minister, who will fly back to the UK overnight, said the return of MPs would go ahead, he made clear his unhappiness with the court's "unusual judgment".

"I strongly disagree with this decision of the Supreme Court," he said.

"I have the utmost respect for our judiciary, I don't think this was the right decision, I think that the prorogation has been used for centuries without this kind of challenge.

"I think the most important thing is we get on and deliver Brexit on October 31, and clearly the claimants in this case are determined to frustrate that and to stop that.

"I think it would be very unfortunate if Parliament made that objective which the people want more difficult but we will get on."