JEREMY Corbyn has said he has not ruled out facilitating a second Scottish independence referendum if he becomes prime minister.

The Labour leader made clear that he would "decide at the time" what to do if Nicola Sturgeon asked for his consent to hold another poll.

However, he stressed that his party did not want a referendum and would be "very clear on why we don't think it's a good idea".

In 2017, Mr Corbyn sparked controversy when he suggested that if Holyrood voted for another vote on Scotland’s future, as it did in March of that year, then it should not be blocked. “I don’t think it’s the job of Westminster or the Labour Party to prevent people holding referenda,” he said.

But before the last Holyrood election Labour gave a "cast-iron guarantee" that it would oppose another referendum.

In an interview with BBC Scotland ahead of this weekend’s start to the Labour conference, Mr Corbyn was asked what he would do if the First Minister, asked for the power to hold another vote on independence; Westminster's consent would be need if any referendum were to be legally binding.

He replied: "We would obviously decide at the time."

Pointing to the £13 billion budget deficit in Scotland, the party leader said a Labour government would invest money in Scotland through a £20bn transformation fund and a £3bn increase in revenue spending.

"Things will be very different in Scotland with an ally in Westminster like a Labour government," he declared.

When he was asked whether he was ruling out giving Ms Sturgeon consent for a referendum to be held, Mr Corbyn replied: "I'm not ruling[it] out; I'm just pointing out the reality.

"We don't want another referendum, we don't think another referendum is a good idea and we'll be very clear on why we don't think it's a good idea.

“What's more important is dealing with child poverty, housing problems and lack of investment in Scotland; 200,000 more children going into poverty has to be dealt with. A referendum will not solve that."

The Scottish Labour manifesto at the 2016 Holyrood election said: “We rule out another referendum on independence during the lifetime of the next Parliament.”

At the general election a year later, then Scottish Labour leader Kezia Dugdale also gave a “cast iron guarantee” that Labour would oppose a second referendum, saying independence would lead to “turbo charged austerity”.

The Scottish Tories said Labour looked “utterly weak” on the constitutional question.

Adam Tomkins, the Scottish Conservative constitution spokesman, said: “Every time Jeremy Corbyn talks about Scotland he gives yet another concession to the SNP.

“It’s more proof that Labour are utterly weak when it comes to Scotland’s place in the UK. Jeremy Corbyn does not care about Scotland and has no interest in standing up to the Nationalists, as this latest gaffe proves,” he added.

Willie Rennie, the Scottish Liberal Democrat leader, said: “This is an extraordinary opinion from Jeremy Corbyn. So many people with moderate and progressive views will be horrified by this careless attitude towards the UK. Liberal Democrats are opposed to independence and opposed to another divisive independence referendum."

He added: "The case against independence is even stronger since the SNP’s Growth Commission admitted what we said about independence in 2014 was right. Brexit also shows that breaking up long standing unions is costly and hard to do.”

Ms Sturgeon is expected to make an announcement on her plans for a future vote on Scotland’s future once the terms of any Brexit deal become clear, which means probably some time in November.

SNP depute leader Keith Brown said: "We already have the democratic mandate to give the people of Scotland a choice over their future – a position backed by the Scottish Parliament. For any Prime Minister to stand in the way of that would be a democratic outrage.

"Of course, it used to be the case that Labour thought the people of Scotland were sovereign and should determine their own future. Now, apparently, it’s down to the whim of the MP for Islington North."

A Scottish Labour spokesperson said: “Like the majority of the people of Scotland, Jeremy Corbyn doesn't want to see a second referendum.

"Jeremy is clear that independence is not in the interests of Scotland and the Scottish people and would lead to intensified and prolonged austerity; something even the SNP Growth Commission now recognises.

“The real divide in Scotland is between the richest and the poorest - not the false division created by another referendum."