JEREMY Corbyn backed Scottish independence during a private conversation with an SNP MP, it has been claimed.

Mhairi Black alleged the UK Labour leader privately told her he supported the break-up of the UK, but added he had since “sold out”.

In an interview with the website HuffPost UK, the Paisley and Renfrewshire South MP said: “I was excited by Jeremy Corbyn for the same reason as all the Labour membership were, but since he has got into that position of power, what’s he done?

“He has had unelected lords in his cabinet. He’s had scandal upon scandal, and don’t get me wrong, I get that there is a whole lot of backbenchers against Jeremy, but he has sold his soul.

“He has sold out in terms of austerity. He has sold out in terms of Scottish independence – because I know that he doesn’t believe the things he says about independence now.”

When Ms Black was asked how she knew Mr Corbyn supported independence, she replied: “From talking to him.”

But she insisted she “couldn’t possibly comment further” and declined to go into any detail about the alleged conversation.

Mr Corbyn has previously argued independence would be “catastrophic” for Scotland.

But he caused controversy last year when he reportedly said holding a second referendum would be “absolutely fine”, placing him at odds with his party in Scotland.

He also famously told The Herald before he was elected leader for the first time: "I'm a socialist not a Unionist."

Labour dismissed the latest claims as “complete nonsense” with no evidence to back them up.

A party source said Mr Corbyn failed to campaign for the Union during the 2014 referendum, but doubted he was naïve enough to have shared his thoughts with Ms Black.

The source said: “Corbyn didn’t lift a finger to help the campaign against independence and is very close allies with people who would happily break up the UK.

“Scottish voters don’t feel they can trust him on the Union, and that remains the greatest challenge for Labour to overcome.

“This certainly won’t help that, even if Mhairi Black’s claim is made up.”

A Labour Party spokeswoman said: "Mhairi Black's claims are complete nonsense."