Jeremy Corbyn has sought to clarify his position on a second Scottish independence referendum, saying Westminster should not block it going ahead but that a breakaway would be "catastrophic".

As Scottish First Minister Nicola Sturgeon prepared to deliver an "important speech" on Monday, with speculation mounting that she could outline plans for a second referendum, Mr Corbyn insisted he was not in favour of another vote.

The Labour leader faced a furious backlash from Labour MPs after telling Press Association Scotland it is "absolutely fine" for another vote to go ahead on Scottish independence.

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Clarifying his position on Monday, he said it would be "wrong" for the UK Parliament to block another vote going ahead if the Scottish Parliament was in favour of it.

He told BBC Radio 4's Today programme: "If the Scottish Parliament decided they wanted to have a referendum then it would be wrong for Westminster to block it.

"But let's be absolutely clear, I do not think there should be another referendum, I think that independence would be economically catastrophic for many people in Scotland, it would lead to a sort of turbo-charged austerity with the levels of income the government has in Scotland and because of the very low oil prices and the high dependency on oil tax income."

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On Saturday, when he was asked if a second independence referendum appeared inevitable given the gulf between Ms Sturgeon's goal of keeping Scotland in the single market and Theresa May's plans for a UK-wide "hard Brexit", Mr Corbyn told PA Scotland: "If a referendum is held then it is absolutely fine, it should be held.

"I don't think it's the job of Westminster or the Labour Party to prevent people holding referenda."