But nationalists must ditch the divisive tactics of the last campaign to capitalise on the current “meltdown” of UK politics, SNP deputy leader Keith Brown will tell the party in a speech today.

The former cabinet secretary will reject claims that Brexit has damaged the case for leaving the UK in a keynote speech in Aberdeen. The SNP has published figures indicating that Brexit preparations are costing Scotland’s public sector 8,000 jobs.

First Minister Nicola Sturgeon is preparing to set out her timetable for a second referendum in the coming weeks.

Keith Brown rejects claims that Britain's difficulties over leaving the EU have weakened the case for Scottish independence. Picture: John Devlin

Pro-Union parties last night dismissed Brown’s claims, insisting that leaving the UK would be “massively more complicated than Brexit” and would mean surrendering a raft of powers to Brussels.

Speaking at a one-day conference in Aberdeen, the SNP Depute Leader will contrast the “narrow isolationism” of Brexit Britain with the opportunity for change offered by independence.

“Many of us who support independence have long viewed Westminster as a failing institution,” he says.

“But even we would have struggled to predict the complete meltdown caused by Brexit.

“Both Westminster parties are falling apart – and every day, we get closer to Brexit with no deal in sight. The costs of a no-deal Brexit are unthinkable.”

Only last week, Finance Secretary Derek Mackay warned that crashing out of the European Union could plunge the country into a recession worse then the financial crash of 2008.

The publicly stated costs of preparing for Brexit currently stands at £4.2 billion. SNP analysis shows Scotland’s share by population would be over £344 million. This would be enough to train the equivalent of nearly 3,500 teachers, 2,400 nurses, and over 1,800 police officers.

Brown slams Labour and the Tories over their support for an end to Freedom of Movement of EU nationals which is expected to mean labour shortages in the key hospitality and rural sectors in Scotland.

“Brexit Britain offers narrow isolationism – while independence offers the opposite,” he says.

“Independence is about Scotland joining Europe and the rest of the world as an equal partner – not about throwing up new barriers like Brexit does.”

Scots voted 55 per cent to 45 per cent in favour of remaining in the UK in the referendum in 2014 and support for a Yes vote has remained at this level.

Brown, a former marine, was tasked with heading up a revived case for independence by Sturgeon a week after being elected as deputy leader last June. He was axed at the time from his cabinet role as Economy Secretary.

Today he will call for an end to the divisive approach of the last independence campaign which split the country amid claims of online harassment and abuse on both sides. “People across Scotland are looking at this chaos unfolding and they’re wondering how it’s even possible,” Brown will say.

“Many who voted No in 2014 are horrified – even if they might not, yet, be prepared to back independence.

“It’s our job to persuade them – with patience, empathy and kindness. Brexit is a symptom of Westminster’s failings as much as the cause – a Tory government, without a mandate in Scotland, delivering Brexit, which was rejected in Scotland. Independence will mean that decisions about Scotland will be made by the people of Scotland.

“People are ready to listen to that case. We need to show why it’s an opportunity worth taking.”

Brown’s view contradicts the report last week by the Scottish Centre on European Relations which indicated that Scottish independence divorce talks would be “much tougher” than Brexit.

And David Duguid, Tory MP for Banff and Buchan branded Brown’s claims “embarrassing”.

“Under the SNP’s plans, Scotland would go straight back into the hated Common Fisheries Policy – handing back control over our waters to the EU. Far from regaining decision-making powers, we would be surrendering them all over again.

“This boomerang attack only goes to show just how utterly out of touch the SNP has become with the north-east and our vital offshore fishing industry.

“He must do better. Mr Brown needs to go home and think again.”

Pamela Nash, chief executive of Scotland in Union, said: “This is a laughable claim from the SNP. Breaking up the world’s most successful union after more than 300 years would be massively more complicated and painful than leaving the EU.

“Independence would be eight times as costly as even the worst-case Brexit, leading to devastating spending cuts and tax rises. That’s why many former Yes voters now want to remain in the UK.”

Convince voters Scottish independence is opposite of Brexit, says Keith Brown