BRITAIN has “nose-dived” in the last 10 years – and Brexit is proof, The Proclaimers have said.

Speaking to the BBC ahead of their upcoming album Dentures Out, the Edinburgh brothers said the UK had been a “diminishing power” since the Second World War.

The new album, Craig and Charlie Reid say, is their most political in decades.

The singers take issue with British nostalgia, saying the Union often has a tendency to wear rose-coloured glasses when looking back.

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Speaking about the group’s 12th studio release, Charlie said: “It's certainly the most political thing we've done for seven or eight albums.

"For the first time ever there's a constant theme in an album we've done.

“A lot of it is about nostalgia, about people looking back and perhaps looking back with rose-coloured glasses or not remembering at all.”

Charlie said such a tendency is especially common in the UK.

Craig added: "I think Britain has been diminishing in power and reach since World War Two but I think that in the last 10 years Britain has nose-dived as regards its own self-worth and certainly in regard to its own place in the community of nations.”

He said Britain is probably in “terminal decline”.

The National: The Proclaimers' new album cover shows dentures in a glass next to a Union flag-covered bedThe Proclaimers' new album cover shows dentures in a glass next to a Union flag-covered bed (Image: Murdo MacLeod)

The brothers believe Brexit has reflected that, with Craig adding that most popular political parties in the UK have shown a “totally inability … to cope with what has happened”.

Speaking about independence, the two well-known Yes supporters said such a vote is “probably more likely now than it was before”.

Among the subjects covered in the new album is the NHS, which Charlie says is “easily the greatest thing that any British government has done”.

Although, he took issue when Cambridgeshire-based Aircraft Restoration Company flew a Spitfire reconnaissance plane with "Thank U NHS" painted under its wings to mark the service's 72nd birthday.

“The irony of [thank you NHS] being painted on the side of a Spitfire plane, which was obviously one of the main killing devices that Britain used in World War Two - thankfully to defend us against the Nazis - was not lost on many of us,” Charlie said.

Ahead of the September 16 release of Dentures Out, Craig and Charlie are on tour, playing new material alongside the classics.

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"500 Miles, Letter from America, Let's Get Married, Sunshine on Leith, we always do them at every show," Charlie said.

"The fact that people still want to hear them 30 years later is great for us and I suppose for the audience it connects them with their own past as well.

"But to do a show without any new songs would not be right because I think as writers we've got better as time's gone on."

Craig added: "We've had a much longer run at it than we thought we would, so now we are at 60 we just want to do the best that we can and do it for as long as we can and to keep enjoying it."