Labour's position on a second independence referendum has again been thrown into confusion ahead of the shadow chancellor's visit north of the Border.

Scottish leader Richard Leonard previously insisted Labour would “categorically” state its opposition to a another vote ahead of any general election.

However this was later undermined by UK shadow chancellor John McDonnell, who said a Labour Government would “consider whatever proposals come from Scotland”.

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Mr Leonard has now stressed he will “fight with every sinew” in his body to make sure another referendum is ruled out in the party’s next manifesto, suggesting the issue is far from settled.

He told the Scottish Parliamentary Journalists’ Association he was "implacably opposed" to a second poll.

He said: “What I’m saying is that I think it’s absolutely essential, and I will fight every step of the way to make sure that the next Labour manifesto, going into the next general election, will contain the same commitment that was in the Labour manifesto going into the 2017 general election.

“And that is a statement of clear opposition to a second independence referendum.”

Mr Leonard said the issue was decided “pretty firmly and clearly” in 2014, while the SNP’s own independence blueprint suggested breaking away from the UK would lead to a decade of austerity.

He argued the “massive political crisis” growing out of Brexit meant even the SNP was moving away from calling a second vote, adding: “I make no apology for reminding people that the economic and monetary integration that we’ve had for 40 years with the EU is nothing compared to the economic and monetary integration we’ve had with the rest of the UK."

He continued: “I don’t think that there’s especially an appetite for it. I’m absolutely implacably opposed to it.

“I will fight with every sinew I’ve got to make sure that that is in the next Labour manifesto – that we will oppose a second independence referendum.”

Asked if he would resign if this was not the case, he dismissed it as a “hypothetical question”, adding: "I am absolutely clear that it was in the 2017 manifesto; it will be in the next Labour general election manifesto."

It comes as Mr McDonnell vowed he would be the most radical Chancellor in post-war Britain, and pledged to deliver an irreversible shift in wealth and power away from London towards Scotland.

Speaking ahead of a two-day campaign tour in Scotland, kicking off in Glasgow this morning, he said: "Scotland has suffered from a near decade of Tory and SNP austerity.

"The Tories at Westminster have imposed the bedroom tax and the rape clause on working class Scots, as well presiding over a surge in food bank use caused by over eight years of austerity.

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"At the same time, the SNP at Holyrood has simply passed on Tory austerity to communities, by bullying councils into making cuts and running down crucial areas like further education, as well as underfunding Scotland's NHS.

"The SNP has also embraced its own version of neoliberalism with the Growth Commission – a blueprint for at least a decade of austerity.

"By contrast Labour in government at Westminster will halt austerity which our manifesto commitments could mean £70bn more for Scotland over two terms.

"As Chancellor, this package will represent the biggest transfer in wealth and power from London to Scotland in post-war Britain.

"The next Labour government will be the most radically reforming one since that of Clement Attlee and Nye Bevan elected in 1945."