The Conservative Government is “making the case for independence” with its attempt to block Scottish efforts to prepare laws for Brexit, the SNP has claimed.

This week, the Supreme Court ruled a key section of the Scottish Government’s Continuity Bill, an alternative Brexit Bill, was outside of Holyrood’s legislative power after a challenge by the UK Government.

Following the ruling, the SNP’s depute leader Keith Brown said it exposed the “astonishing lengths” the UK Government have gone to in a bid to undermine devolution.

Mr Brown said: “With every day that passes, the Tories are making the case for independence.

“The UK Government’s behaviour over the Continuity Bill – exposed this week by the UK Supreme Court – shows the utter contempt with which they are treating Scotland.

“With the UK Government’s approach to Brexit in complete and utter chaos, it’s no wonder the Scottish Parliament didn’t trust Westminster to prepare our laws for life after Brexit.

“But the astonishing lengths the Tories have went to tie Holyrood’s hands should shock all democrats.”

He added: “Scotland never voted for Brexit but we’re having a one-size-fits-all approach imposed on us by a Tory party who simply can’t be trusted.

“It is now clearer than ever that Westminster is simply not working for us and that only independence will put Scotland’s future in Scotland’s hands.”

Tory constitutional spokesman Adam Tomkins responded said: “This is an astonishing assertion from the SNP and one that is demonstrably false.

“The Supreme Court ruled, conclusively, that the SNP’s Continuity Bill was largely incompetent.

“Once again the SNP demonstrates that it cannot accept a verdict it disagrees with and will use any tactic to push for independence.”

Most MSPs had voted in favour of the legislation put forward by Scottish ministers as an alternative to the EU Withdrawal Act, which was then challenged by the UK Government.

The Scottish Conservatives opposed the Bill and have now said it should be scrapped.

Speaking after the court’s decision, Mr Tomkins said: “Today’s Supreme Court ruling is a clear, unambiguous and of course unanimous judicial vindication for those of us who considered that the SNP’s so-called continuity bill unlawful.”

Mr Tomkins claimed the Supreme Court “has eviscerated the Bill, leaving it in tatters”.

But Scotland’s top law officer, Lord Advocate James Wolffe QC, told him: “It’s clear that at the time this Parliament passed the bill, it was – in its entirety with the exception of one section – within the competence of this Parliament.”

He told MSPs the EU Withdrawal Act – which was passed by Westminster but which the Scottish Parliament did not consent to – had subsequently imposed “new limits on the legislative competence of this Parliament”.

Constitutional Relations Secretary Mike Russell branded the legal challenge an “act of constitutional vandalism” by the UK Government and said he would speak with other parties about amending the Bill.

He added: “For the first time ever, UK law officers delayed an act of the Scottish Parliament from becoming law by referring it to the Supreme Court.

“Then the UK Government, for the first time ever, invited the UK Parliament to pass a Bill which they knew would cut the powers of the Scottish Parliament without its consent.”