A LEGAL challenge to ensure Boris Johnson "obeys the law" and seeks an extension to the UK's exit from the EU is expected to land on Scottish courts tomorrow.

The case lodged at the Court of Session is being taken by businessman Dale Vince, QC Jo Maugham and QC and SNP MP Joanna Cherry.

Mr Maugham says that a short 'directions' court appearance is expected tomorrow, before a substantive hearing on Thursday in the Outer House of the Court of Session.

A potential appeal by other side could be heard on October 8 with a potential Supreme Court hearing on the week commencing October 14.

Mr Johnson ramped up speculation he is planning to bypass a law that stops the UK crashing out of the EU without a deal over the weekend.

He told the BBC’s The Andrew Marr Show that Britain can still leave the bloc on October 31 despite the passing of the Benn Act, which aims to prevent a no-deal Brexit by forcing him to ask Brussels for a delay.

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Ms Cherry earlier said the legal action has commenced "to make sure the Prime Minister obeys the law and the will of Parliament to seek an extension of Article 50 period after October 19 to avoid No Deal Brexit."

The new court action has been funded by Mr Vince, a millionaire businessman and political donor who founded the green energy company Ecotricity and Mr Maugham, director of the Good Law Project.

Mr Maugham was one of the driving forces behind the legal battle in Scotland to stop Boris Johnson forcing through a no-deal Brexit by proroguing Parliament.

Mr Maugham said: "At the heart of the case is the question how you fit the PM's very square peg - 'we will leave on 31 October come what may' - into a very round hole - the Benn Act compels the PM to ask for an extension."

The prime minister has previously said he would "rather be dead in a ditch" than ask for a further delay beyond October 31.

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The group is seeking a judgment from Scotland's highest court – the Court of Session's Inner House – which ruled earlier this month that Boris Johnson's proroguing of Parliament was unlawful. That decision was echoed unanimously by the Supreme Court.

Those behind the case want the court to use a special power - the "nobile officium" - to effectively sign the letter to the EU on behalf of the prime minister, should he refuse to do so himself.

Despite controversy after he repeatedly labelled the Benn Act the “surrender bill”, Johnson described himself as a “model of restraint” in what has been described as an increasingly toxic political atmosphere.