A FORMER Tory MSP has said a second independence referendum is going to have to be held “eventually” – and that deploying “muscular Unionism” will lead to the break-up of the UK.

Adam Tomkins, Professor of Public Law at the University of Glasgow, who stepped down at May’s election, argued the preservation of the UK was currently under more under threat from Unionists than nationalists.

Speaking at a conference examining Boris Johnson’s constitutional reform agenda on Friday, he said Scottish politics would remain stuck unless either “the Union crumbles” or the nationalist movement “splinters or fractures”.

He added: “There isn’t going to be a second independence referendum any time soon, but there probably is going to have to be a second referendum eventually. Nobody knows exactly when.”

Tomkins said there were three schools of thought on how to save the Union which are “represented at the moment at the top of UK Government”.

He outlined one as doing nothing in the expectation support for independence will eventually peter out, while another approach is to spend time showing Scots the “value of the Union”, including through the new spending powers to spend in devolved areas introduced in the Internal Market Act.

While the idea of “muscular Unionism” is to make the Union much more visible and “take back control of the agenda”, he added Tomkins said: “The Union is under much greater threat from Unionists than it is from nationalists at the moment.

“I have always sort of thought that one way or other the Union would probably survive the threat of Scottish nationalists. I don’t think it will survive the threat of English nationalists.

“And the very worst weapon you could possibly pick up to fight Scottish nationalism, if that’s what you want to do, is English nationalism. That’s what Unionists increasingly are doing – that is what muscular Unionism is. Muscular Unionism is a vision of the future of the United Kingdom which doesn’t understand we are a union state and doesn’t understand the difference between England and Britain. If that’s where you go, you will break the country up.”

Examples of “muscular Unionism” reported in recent weeks include the Earl and Countess of Strathearn being deployed north of the Border to win over Scots and British diplomats being told to stop referring to the UK as a union of four nations, focusing on the Union as a single country.

At the conference held by the Constitution Unit, the Department of Politics & International Relations at the University of Oxford and UK in a Changing Europe, Tomkins spelled out the consequences for the UK if Scotland left.

He said: “To lose 10% of your population, to lose a third of your land mass, to lose two-thirds of your coastline, to lose all of the Nato defences of the high north which are located in north of Scotland, to say nothing of the only place on these islands where we can have a nuclear deterrent based which is in Faslane, where it is at the moment, would be catastrophic for the UK. There is no question about that.”