Douglas Alexander has warned that the SNP risks repeating a "fatal Tory error" of seeing a referendum as a solution to "a party problem".

The former Labour big hitter - now an international scholar and the advisor to a global law firm - was defeated at the last general election by a nationalist surge and has stayed away from the front line ever since.

However, Mr Alexander has broken his silence with a new essay on post-Brexit Scottish politics in which he compares Nicola Sturgeon's SNP demanding a vote on independence with David Cameron's fateful decision to call last year's EU referendum.

He wrote: "We have just witnessed one form of nationalism take us out of Europe with little thought for the consequences, so we should be wary of another form of nationalism repeating a similar mistake in Scotland.

"Little wonder a majority of Scots are not demanding another independence referendum at this time and the opinion polls fail to show significantly increased support for independence since the Brexit vote last June.

Yet, almost 100,000 supporters have joined the SNP following the Scottish independence referendum, which helps explain why the First Minister continues to assert that for her, independence ‘ultimately transcends the issues of Brexit, of oil, of national wealth and balance sheets and of passing political fads and trends”. It seems evident therefore that for the First Minister and her Party, the real issue is not so much the terms of the deal, but the level of the polls.

"My honest worry is that the SNP now risks replicating David Cameron's fatal error -starting off trying to solve a party problem and ending up creating a far bigger country problem."

Douglas Alexander

The Herald: DOUGLAS ALEXANDER: Favours a quick dash to the polls

Mr Alexander's essay is published later this month as part of a major new book bringing together academic voices to try and understand where Scotland can go after Brexit.

Reflecting several of the themes first explored by The Herald's ground-breaking "Beyond Brexit" series, "Scotland, the UK and Brexit: A Guide to the Future" is edited by commentator Gerry Hassan and Russell Gunson, director of the cross-party progressive think tank IPPR Scotland.

It looks at everything from a differentiated Scottish membership of the EU - first mooted in this paper and since adopted as SNP policy- to the niceties of fishing and farming in a post-Brexit age.

However, Mr Alexander gives the most political essay, arguing against what he sees as the divisions brought by a new call for a referendum he does not believe Scottish nationalists can win.

Mr Alexander argues that a new settlement is possible after Brexit. He makes three specific proposals. The first is that Scotland should get all the EU powers on devolved areas such as fishing and farming. Second, he backs calls for Scotland to be able to issue work permits and have a differentiated immigration policy - something suggested by the SNP and, for London, by Labour Mayor Sadiq Khan. And third he calls for Scotland to be able to forge ahead with bilateral relations with the EU on devolved issues, including, crucially higher education education.

Mr Alexander wrote: "Constantly threatening an independence referendum in the face of the economic evidence and without offering answers to reasonable questions doesn't enhance the First Minister's credibility for the discussions ahead - it diminishes it.

"Today we need more new thinking, and less of just the same old threats. Why would we choose to add greater insecurity and uncertainty to the insecurity and uncertainty already created by Brexit? Why would we choose an approach that guarantees division and rancour rather than an approach that could build consensus by consent?

"The reality is that millions of Scots today feel squeezed between nationalist narratives North and South of the border and identify with neither. "

Dr Hassan, co-editor of the new book, said: "Brexit is the biggest geo-political challenge to the UK in post-war times.

"In the year since the Brexit vote the UK Government has shown no propensity to undertake or understand the strategic consequences and choices which Brexit forces the UK to face up to.

"Brexit also throws up questions for all Scotland’s political parties and traditions. It requires the UK Government and pro-union parties to address how Scotland’s distinctive voice and democratic wish to remain in the EU can be acknowledged and respected.

"But equally it throws up huge issues for the Scottish Government, central of which is, if the UK says no to any kind of differentiated Brexit, what does a different version of independence look like. and just as importantly, how and when does it emerge?"

Scotland, the UK and Brexit: A Guide to the Future, is edited by Gerry Hassan and Russell Gunson, and published by Luath Press in association with IPPR Scotland £12.99 on June 30th.