A LABOUR government at Westminster would block a straight Yes/No question in a second independence referendum, it has emerged.

Shadow Scottish minister Paul Sweeney said there should be a multiple-choice question instead, with a federal United Kingdom as one of the options.

The Glasgow North East MP told BBC Radio Scotland a Labour government would deliver “a radical transformation and federate the United Kingdom”.

He said: “That of course should be a question in that referendum in future. It shouldn’t just be a binary referendum, and we’ll be backing that option.”

Ahead of the 2014 referendum, then Tory Prime Minister David Cameron gave the SNP government a free hand on the question, timing and franchise for the referendum.

It allowed Alex Salmond to decide on a Yes/No format, and to campaign as Yes.

READ MORE: Ruth Davidson accuses Labour of 'rank betrayal' over independence referendum

Mr Sweeney’s remarks suggest a Labour government would take a very different approach and try to set the terms on a second vote.

However a federal system, in which the regions of England were also given new powers alongside the devolved nations, could depend on votes passing elsewhere in the UK.

As that could not be guaranteed, a Scottish vote for a federal system might go nowhere.

When the last Labour government tried to move towards a federal system in 2004 with an elected assembly for North East England, voters rejected it 78-22 in a referendum.

Labour MSP Neil Findlay, Mr Corbyn's campaign manager in the party's leadership contest, also said it would be "democratic" to allow Indyref2 if there was a mandate for it.

However he said there should also be a "confirmatory vote of the Scottish people" on the outcome of any independence negotiations.

He told BBC Radio Scotland: "I don’t want a second referendum. I would campaign against it. I would campaign against independence as vociferously as I did the last time.

“However if there’s a majority in the Scottish Parliament and parties have stood on a manifesto saying that they will have a referendum, and if those parties get a majority, then I think it’s just democratic to say that they would then be allowed to negotiate with the UK government to have that referendum.

“I think in that process, any negotiated that they had would have to come back to a confirmatory vote of the Scottish people."

The pair were speaking after Scottish Labour was convulsed by a row over whether to allow a second independence referendum sparked by shadow chancellor John McDonnell.

In two appearances on the Edinburgh Fringe this week, he said a Labour government at Westminster would not block a referendum if Holyrood asked for it.

He said: "It will be for the Scottish Parliament and the Scottish people to decide that. We would not block something like that.

“We would let the Scottish people decide. That's democracy.”

That flatly contradicted Scottish Labour leader Richard Leonard, who in March said that Labour would block Indyref2, even if a majority MSPs requested it.

READ MORE: John McDonnell ignores Richard Leonard and keeps independence referendum on the table

Despite Mr Leonard meeting Mr McDonnell on Wednesday morning and stressing the 2014 vote should be a once-in-a-generation event, Mr McDonnell stuck to his position.

He said: “If, after a few years, people want to come back and say they want to test the water on an independence referendum then fair enough, that’s up to the Scottish people and the Scottish Parliament. I’m not here to block a democratic exercise by any means.”

“I’m not being set up by Nicola Sturgeon because that’s what she’s trying to do.

“She’s trying to say it’s the big bad English yet again trying to prevent us holding a referendum. No we’re not. What we’re saying is it’s unnecessary.

“We will campaign against having a referendum, but we are not using parliamentary devices to block it - it’s as simple as that.”

The Tory government has so far refused to grant Holyrood the power to hold a referendum under Section 30 of the 1998 Scotland Act.