THE author of the famous McCrone oil report has said refusing indyref2 would be wrong if Scotland wants a fresh vote.

Professor Gavin McCrone said the idea of the independence referendum being a once in a generation event is now “simply not credible” after the UK left the EU without taking ­account of the results in Scotland.

The economist, whose book ­examining the economics of ­Scottish independence after Brexit will be published next month, also argued the country would face a “very tough” period after a Yes vote – but could do well in the long-run in a similar way to the example of Ireland.

McCrone has outlined his ­concerns over issues such as ­balancing the budget and currency in After ­Brexit: The Economics Of Scottish ­Independence, but told the Sunday National a referendum should be held if consistent polls indicate majority support for independence.

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“I would have thought it would be a bit ridiculous to refuse a referendum if there was continued showing in the polls wanting it,” he said. “If it was refused after a lot of polls showed the population of Scotland wanted it, I think that would be wrong and liable to lead to a lot of trouble.”

McCrone ruled out the idea of ­requiring any kind of “super ­majority”, as happened in the 1979 referendum on Scottish devolution, which required a majority which was at least 40% of the electorate.

“That might have been an idea at one time, but with the EU ­referendum just based on a simple majority, even quite a small one I think it would be very unpopular and would be ­resisted,” he said.

He also questioned the idea of ­federalism being offered as an ­alternative to independence and said it was not clear what extra powers Scotland would be offered.

“In any case I think the ­Scottish issue is going to be addressed more quickly than could be done ­trying to get agreement to federalism ­throughout the whole of the UK,” he added.

McCrone said he believed the UK should have stayed in the EU and said the consequences of Brexit have yet to be fully seen, as it has been masked by Covid.

He said: “The danger is the long-term damage because, for example, overseas investment on which we have relied very heavily after the ­collapse of our traditional industries is likely to slacken off as a result of Brexit.

“One of the main attractions that we used to attract overseas ­investment was that they could ­export freely to Europe without any restrictions and that will no longer be the case.

“But there is also a problem with population, as we have a declining population in Scotland.

“The people who have come in from the European Union have filled a lot of skilled jobs in the NHS and elsewhere and the unskilled ones have done things like help the ­harvest of the soft fruits, for example.

“We will find it is difficult without that, I think that will also affect our rate of economic growth.”

McCrone argued Scotland now faced a difficult choice in the future between independence and staying within the UK post-Brexit.

He said: “I deliberately don’t take sides in that as I wanted my book to be impartial, rather than to try and campaign for one side or another.”

He added: “An independent ­Scotland would have a bit of a ­struggle financially to begin with anyway, as the budget would be in deficit.

“I think there would have to be a Scottish currency, which would ­probably depreciate a bit. And that might help to stimulate growth and make it possible to pay all these things more easily.

“But I think there would be a very tough period to begin with.”

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However he said: “I think it is possible to argue that Scotland might do better in the very long run, but that would depend on how sensible the government was.

“It took Ireland 30 years to sort itself out and start making the right decisions. It has done very well in the end and hopefully it wouldn’t take Scotland as long as that – but I think it would take a while.”

An SNP spokesperson said: “The people of Scotland voted overwhelmingly in favour of pro-independence parties in the elections last May ­delivering a cast-iron mandate for an independence referendum.

“Any attempt to deny the ­democratic will of the people of ­Scotland is an affront to democracy.”