Andrew Wilson, the former SNP MP who produced the Growth Commission report for the nationalists, defending his work from critics who said it was too cautious and would damage the case for independence.

Mr Wilson’s report called for an independent Scotland to continue to use the pound and only move to a new Scottish currency if a number of economic tests are met.

Speaking to the BBC, he said the Growth Commission offered a "more balanced view of the future, which says independence will take significant effort but that effort will be worth it."

Andrew Wilson, the former SNP MP who produced the Growth Commission report for the nationalists, defending his work from critics who said it was too cautious and would damage the case for independence. Picture: PA Wire

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"We want to be fast growing, we want our trade to diversify from overdependence on one of the slowest growing economies in the developed world.

"But transitions need to be managed and they need to be managed honestly so that people can say as we're going through it we knew this was what was going to happen.

"One of the big lessons from Brexit is effectively how not to do change, how not to manage transitions."

Mr Wilson’s critics have dubbed his report a ‘cuts commission’ over its call for an independent Scotland to cut its budget deficit in half within ten years, requiring tough spending decisions.

Tackling the criticism head on, he told the BBC’s Douglas Fraser that a new state would have to "fund public services sustainably" and prove to international markets that "we are a good counterparty that will pay them back".

Mr Wilson added that he is "not seeking personal popularity - I'm seeking to win".

"We need to win by persuading people that are currently not convinced by the case, and all of the polling evidence is suggesting they are persuaded by a message that says the case for Britain is collapsing and the case for Scotland is developing,” he added.

"We have an argument that independence will be an effort. Money doesn't drop out a tree, Rome isn't built in a day, nothing falls in your lap. That's not real life. You don't win the lottery.

"What happens is you get a tool box and the ability to work, and that work will be worth it. It's going to be an effort, it's going to be a challenge, but all of the evidence of history in the small best performing countries in the world is that that challenge is worth it."

Labour Finance spokesperson James Kelly said: “Andrew Wilson’s Growth Commission is really just a cuts commission, proposing a decade of unprecedented austerity for Scotland outside of the UK.

“It would be devastating for jobs, public services and social security in Scotland.

Scottish Liberal Democrat leader Willie Rennie said: "Andrew Wilson is an intelligent person and rightly acknowledges that the Scottish and UK economies are tightly bound together.

"With the chaos of Brexit, the last thing we need is more constitutional and economic upheaval with independence.

"What the Scottish public want is a government that is focused on improving public services."

'Significant effort' for Scotland to exit UK, Growth Commission author says