Writing for Holyrood, McLeish said that it is “not the time” to settle Scotland’s constitutional and political future, and added that referenda can be a “dangerous” and “unpredictable” constitutional tool to deploy.

He continued: “…their use should be pursued with great care and caution and a minimum number of conditions should be in place. There should be a real desire on behalf of the public. There should be some form of political consensus that a vote is required. A broad range of options should be available. The views of the wider Union have to be factored into the debate. More importantly, a vote should only be held after a wide-ranging and well-informed debate.

“None of these conditions is currently in place.”

He also criticised Labour for creating policy “on the hoof,” and urged the party to “rethink and reprioritise” its own constitutional thinking.

He said: “At the heart of Labour’s dilemma is the failure to embrace a coherent, modern, and post-devolution policy, philosophy and strategy for the constitutional future of Scotland. Without this, recent events could happen again. There is currently no road map, no signposting and consequently, policy can be made on the hoof and tactics which look attractive at a moment in time can quickly unravel...credibility, confidence and consistency matter in politics.”

He continued: ”Labour has to confront the SNP not by posturing but with new policy thinking; by embracing a much more radical and inclusive political strategy; by regrouping and refocusing its campaign efforts and intellectual energy and by promoting a different future for Scotland.

“This approach acknowledges the importance of the Union and therefore the role of the UK Government and Parliament. It is a unifying strategy not a divisive one.”