SCOTLAND'S highest civil court has ruled Boris Johnson's decision to suspend Parliament for five weeks ahead of Brexit was unlawful. 

There were gasps when the decision was read out at the Court of Session in Edinburgh. 

The UK Government will appeal the decision to the UK Supreme Court for a definitive ruling. 

READ MORE: LIVE: Parliament suspension ruled 'unlawful'

The three Scottish judges said they would now "make an Order declaring that the Prime Minister’s advice to HM the Queen and the prorogation which followed thereon was unlawful and is thus null and of no effect". 

A cross-party group of more than 70 MPs and peers led by SNP MP Joanna Cherry QC had asked the court to rule Mr Johnson exceeded his powers when he asked the Queen to prorogue parliament on August 28. 

READ MORE: The Court of Session's damning statement on Boris Johnson's 'unlawful' decision

They appealed to the court's Inner House after Lord Doherty initially insisted the move was "political territory" and could not be measured against legal standards. 

A panel of three appeal judges — including the Lord President, Lord Carloway, Scotland's most senior judge — have now backed the campaigners' case. 

Following the decision, Ms Cherry called for Parliament to be immediately recalled. 

She said: "Now, for every moment Parliament remains prorogued, the British Government are breaking the law. 

"So we, as politicians, are calling for Parliament to be recalled so that we can get on with scrutinising what this Government is up to in relation to Brexit. 

"But as a Scottish MP and a Scottish lawyer, I'm very proud that Scotland's highest court has made this unanimous ruling."

She added: "This is probably the most significant constitutional law decision of the last century across the jurisdictions of the United Kingdom, and it will have major repercussions."

The prorogation began on Monday night amid chaotic scenes in the Commons and is expected to continue in the meantime.

The issue is due to come before the UK Supreme Court next Tuesday.

A summary of the Court of Session ruling states that all three judges "have decided that the PM's advice to HM the Queen is justiciable, that it was motivated by the improper purpose of stymying Parliament and that it, and what has followed from it, is unlawful". 

The Lord President said the circumstances of the decision, and the content of documents lodged at the court by the UK Government, demonstrated that the true reason to suspend Westminster was to "stymie parliamentary scrutiny of the executive". 

Lord Brodie said it was an "egregious case of a clear failure to comply with generally accepted standards of behaviour of public authorities", the summary added.

He said it "was to be inferred that the principal reasons for the prorogation were to prevent or impede Parliament holding the executive to account and legislation with regard to Brexit, and to allow the executive to pursue a policy of a no-deal Brexit without further parliamentary interference".

Lord Drummond Young said the circumstances of the prorogation "showed that the purpose was to prevent such scrutiny". 

The summary of his ruling added: "The documents provided showed no other explanation for this. 

"The only inference that could be drawn was that the UK Government and the Prime Minister wished to restrict Parliament."

Delivering the ruling at the Court of Session, Lord Carloway said: "Each opinion expresses the view that the advice given by the Government to Her Majesty the Queen to prorogue Parliament from September 9 to October 14 was unlawful, and that therefore the prorogation itself was unlawful. 

"The court is conscious that its view differs from that of the Divisional Court of the Queen's Bench Division in England and Wales. 

"The matter is likely, therefore, to require resolution by the UK Supreme Court."