THE LibDems have been told that their plans for a federal United Kingdom are a “non-starter” that would “realistically” never happen by two top experts.

The first comment came from eminent Scottish historian Sir Tom Devine, who told The National that the party’s plans for federalism would be “virtually impossible” to establish through the Westminster legislature.

Devine’s comments came after the publication of a report from Professor Ciaran Martin, a former top civil servant and engineer of the Edinburgh Agreement, in which he argued it was “simply impossible to see democratic consent materialising for such a proposal”.

The LibDems announced their plans for federalism in the UK alongside the release of a booklet entitled Bring Our Country Together.

Published on April 9, the party’s plans include bringing the Sewel Convention into law, introducing an elected House of Lords, a change in the Westminster voting system, and the creation of a UK-wide “council of ministers”.

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However, Devine told The National that the Tory government would not be willing to sacrifice the powers necessary to implement the suggested changes.

He said: “I think [federalism] is a non-starter because of the sheer size of England and because it would lead to a challenge of the old tradition, in England, of the Crown and Parliament, which would have to give up some powers. They would not be willing to do that in the current political context in the UK.”

Asked about former LibDem leader and current life peer Menzies Campbell’s (below) claim that Scotland could be a “guiding light” on the UK’s path to federalism, Devine was unconvinced.

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He said: “You have to remember the Liberal Democrats’ track record. They’ve always wanted in recent years a federal solution, and that’s why I would like to see their response to Professor Martin’s critique of a federal solution in the present political circumstances.

“There’s no interest in it whatsoever in England, and remember at the same time there’s a fair degree of resentment about Scotland, especially among Tory ranks in England, that would make it difficult, if not impossible.

“Even if the Tory Cabinet wished to do it, [it would be] virtually impossible to negotiate a federal solution through the Westminster Parliament.”

In challenging the LibDems to respond, Devine echoed his own comments in his foreword to Martin’s report, entitled Resist, Reform, or Re-run? Short- and long-term reflections on Scotland and independence referendums.

Devine wrote: “There is at present much talk from the Labour Party and the Liberal Democrats about the possibility of federalism in the UK as an alternative to a Scottish divorce. They would be well advised to read Professor Martin’s shrewd assessment of the grave obstacles to such an option before proceeding further down that particular track.”

The Scottish LibDems declined to comment after multiple requests from The National.

In his report, Martin, now a professor of practice in the management of public organisations at the University of Oxford’s Blavatnik School of Government, argues that a federal UK would “realistically” never happen.

The former Cabinet Office constitution director goes on: “Federalism would require the abolition of the ancient doctrine of parliamentary sovereignty. It is worth explaining why.

“When Gordon Brown was preparing his package of constitutional reforms, on becoming Prime Minister in 2007, one of those he most wanted to introduce was a law to make the Scottish parliament permanent. He was quickly, and correctly, advised that such a measure was absolutely impossible.

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“Parliament is sovereign, and a future parliament cannot be bound, save by treaties with other sovereign nations. There is no lawful way of telling the UK parliament that it can’t abolish the Scottish parliament, or of curtailing its powers if it feels like doing so in the future. That is not the case in properly federal countries like the United States. So, for true federalism, parliamentary sovereignty would have to go.”

Martin says that parliamentary sovereignty has been the “bedrock” of the English constitution for centuries and so a referendum would be needed to change it.

He adds: “It is nearly impossible to see the same English voters [who voted for Brexit] turning out in a referendum to limit the powers of the London parliament in perpetuity.”

Martin also argues that Scotland would be unlikely to vote for the change, as “devo-max” is much less popular as an option than it was in 2014. He says a move to federalism without the consent of all four nations would be problematic for the same reasons as Brexit, with the larger England imposing its will on the others.

The professor writes: “If one of the senior pro-Brexit leaders were to say in public that he or she was willing to recommend the renunciation of parliamentary sovereignty, federalism might stand a chance.

“But even then, the union with Scotland, unlike separation from Brussels, is not an issue that excites the English popular vote.”