Jeremy Corbyn has claimed it is “not up” to the UK parliament to block another referendum on Scottish independence.
The Labour leader stressed he is “not in support” of Scotland breaking away from the UK, but added MPs at Westminster should not prevent another poll taking place.
John McDonnell, Labour’s shadow chancellor, recently stated the party “would not block” a Scottish independence vote in comments that prompted an angry backlash from Scottish Labour leader Richard Leonard.
Asked whether he agreed with Mr McDonnell’s comments on Thursday, Mr Corbyn replied: “It’s not up to parliament to block it, but it’s up to parliament to make a point about whether it’s a good idea or not.
“I do not think it’s a good idea.”
Mr Corbyn, who has urged rival parties to make him temporary prime minister, also failed to confirm, when challenged, whether a future Labour government would try and block a second independence poll.
“I would advise that we don’t have another referendum, I’m not in support of Scottish independence,” he added.
“What I am in support of is justice for Scotland and that means investment in Scotland by a Labour government for the whole of the UK.”
Referring to the 2014 poll, which “No” won by 55%-45%, the Labour leader added: “The referendum did take place and a decision was reached on that.
“What I’d much rather is a Labour government given the chance to ensure that Scotland also gets the investment it needs, also gets the social justice it needs, and also gets the job opportunities for young people which have been denied.”
Mr Corbyn’s comments were welcomed by Scottish First Minister Nicola Sturgeon, who has already promised to hold another independence referendum before the end of the current Scottish parliamentary term in May 2021.
She posted on Twitter: “I’m not Jeremy Corbyn’s biggest fan but on this he’s right.
“It is legitimate to oppose independence and to argue against a referendum – it’s not legitimate for Westminster to block a democratic mandate and a majority vote in @scotparl for #indyref2.”
Responding to Mr Corbyn’s remarks, a Scottish Labour spokesperson said: “Jeremy Corbyn and Richard Leonard have made clear that there is no economic case for independence, especially with the SNP’s new position of ditching the pound and new policy of turbo-charged austerity to bear down on the deficit.
“What Scotland needs is radical reforming Labour Governments at Holyrood and Westminster.”
Scottish Conservative deputy leader Jackson Carlaw accused Mr Corbyn of having “surrendered on a second independence referendum”.
He said: “Both he and John McDonnell are preparing to hand Nicola Sturgeon the referendum she wants in exchange for SNP support for a Labour government.
“Scottish Labour has been left dangling in the breeze – they are utterly irrelevant, even to their own party.”
Scottish Liberal Democrat leader Willie Rennie said: “I feel sorry for Scottish Labour voters.
“They’ve been hung out to dry time and time again by a leader who gets it wrong on independence and wrong on Brexit.”
Legally, the Scottish government can only stage an official referendum if the UK government gives it the powers under section 30 of the Scotland Act.
Prime Minister Boris Johnson has said there is “no reason” for Scottish people to have another vote, and that the 2014 poll was an “historic” and “once in a generation” vote.