Media playback is unsupported on your device Media caption Salmond: Holyrood 'could provoke crisis' over Brexit

A constitutional crisis over Brexit could be an "extremely good thing for Scotland", according to Alex Salmond.

The former first minister said it would put Nicola Sturgeon in a powerful position in negotiations over the UK's exit from the European Union.

His comments came ahead of the UK's biggest constitutional case in decades.

The Supreme Court is due to decide how the UK government can trigger Article 50 of the Lisbon Treaty, beginning the process of leaving the EU.

In the case that will begin on Monday, it will also hear evidence on whether Holyrood should give its consent to the process.

On the BBC's Sunday Politics Scotland, Mr Salmond was asked what would happen if the judges ruled in favour of a legislative consent motion.

He said: "It would certainly be a constitutional crisis that would have to be resolved.

"It's true that the House of Commons could try to invoke an override clause but of course you've got to remember that the House of Commons, the MPs, are more or less lined up in favour of Brexit because of the result of the referendum.

"But that's an altogether different thing if you start saying we're going to overturn a legislative consent motion or for that matter have a guillotine in constitutional legislation. The votes change given the question being asked.

"And certainly it would result in a constitutional crisis and that crisis might be an extremely good thing for Scotland because it would put us in an extremely powerful position in terms of securing the interests of Scotland in the negotiations."

'Out of step'

UK chancellor Philip Hammond angered the Scottish government last week when he appeared to rule out a special deal for Scotland in Brexit negotiations during the visit north of the border.

Mr Salmond, the SNP's foreign affairs spokesman at Westminster, predicted that Mr Hammond would "beat a road back to Edinburgh and adopt an altogether different tone" if the Supreme Court ruled in favour of a legislative consent motion.

The Scottish Conservatives branded Mr Salmond's comments a "shameless admission".

Their chief whip John Lamont said: "This is Alex Salmond confirming what we already knew. The SNP is quite happy with constitutional upheaval so long as it forwards its separation goals.

"This is a shameless admission, and perhaps explains why the SNP didn't bother campaigning hard during the EU referendum."

European issue

Scottish Labour leader Kezia Dugdale said it proved the SNP "thrives" on constitutional crisis.

She said both the Conservatives and the SNP were putting the union at risk.

"More than ever, we have two governing parties in Scotland that are out of step with what the majority of people in Scotland want," she said.

"The Tories want Scotland in the UK and out of Europe, and the SNP wants Scotland in the EU, but out of the UK. Continuing to pull our country in each of these directions risks breaking the union once and for all."

The leader of the Scottish Liberal Democrats Willie Rennie MSP said: "Alex Salmond's comments confirm that the SNP are only using the European issue to advance independence."