THE idea that there is a "unifying sense of Britishness simply isn't true anymore", Michael Russell has said.

The SNP president made the comments after an academic suggested that Westminster politicians are failing to understand the differences between the four UK nations.

Professor Alisa Henderson, of the University of Edinburgh, warned that the politicians, the media and academics are often “serially anglo-centric”.

She said UK ministers were particularly guilty of this view, saying they have “routinely refused” to acknowledge whether policies applied to England or all countries in the UK.

Professor Henderson, writing in UK in a Changing Europe: British Politics after Brexit, said there is “very real differentiation, not just in electoral preferences but in political ideals” across the four nations of the United Kingdom.

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She said: “Separate discussions in Scotland, Wales, Northern Ireland, and England often comprise four completely different debates, bearing little relation to any of the political arguments occurring outside those borders.

“And on those occasions when we are having the same argument — over Brexit, for example — we often come to different conclusions.”

Professor Henderson said part of the issue in recognising these identities centred around the fact that efforts to understand the British state were “serially Anglo-centric”.

She continued: “First, the very label ‘British’ politics is symptomatic of a series of other elisions and omissions committed within the Anglo-British state, where England is simultaneously the point of reference but largely ignored as a political community.

“Serial offenders here are UK ministers and government departments that routinely refuse to acknowledge when they are announcing policy developments for the state as a whole or England-alone.

“This is coupled with an Anglo-British media that sees little merit in clarifying these distinctions to its audiences (which has on occasional earned a warning from Ofcom).

“This is not just practitioners at fault here. Academics routinely plonk ‘British identity’ into regressions and find results (people who feel British think/do this) without ever acknowledging that British identity works in different ways in different parts of the state.”

Responding to the comments, SNP chief Russell told The National that it shows how many politicians in UK politics are not facing up to "reality".

He said: "It points to something that is undoubtedly true, both in academic life and political life, that the assumption that there is some sort of shared Britishness needs to be questioned.

"And that's not a criticism, that's just an observation. It's not criticizing anybody, it's saying that the political concerns of various parts of the UK have diverged and to recognise that is to recognise reality - and it's always best to recognise reality.

"My experience is that Westminster politicians don't recognise reality, that they live in a fantasy world where everything is as it might have been a half a century or more ago.

"It's not threatening to them, it's just true that each part of these islands have developed differently and if they are relaxed about that we can get on very well on a basis of equality.

"That is the basis of which we can build a good, new relationship."

Asked about Professor Henderson's comments that ignorance by politicians has been made worse by the media, Russell said "part of it is laziness".

He added that "things have changed" and urged people to recognise that change.

Talking about muscular Unionism, he said that is "hankering after a path that is gone".

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"That's fantasy, that's not reality," he said. "I'm a great believer of living in the real world and those who don't live in that world don't communicate with people - they don't understand it.

"The inevitability is that we are growing apart politically. That's how it's been before devolution and the conseunces of that is that we are all going to find our own way in the world and they [Westminster] are going to have to recognise that. And they'll need to recognise that as much as anyone else.

"The idea that there is some unifying sense of Britishness simply isn't true anymore and it's best for all of us to admit it."

The UK Government has been contacted for comment.