PETE Wishart has described Sir John Major's proposal for two independence referendums as an "absurd" proposition which would be managed in such a way by the pro-Union parties to make sure the independence side lost the second vital ballot.

The SNP's longest-serving MP gave his views after the former Conservative prime minister said another vote could take place if there was then a confirmatory ballot.

But Wishart set out what he believed were the key dangers for independence supporters for such a plan.

"When there will be a future independence referendum is something that will be agreed by both the Scottish Government and the UK Government. It will have nothing to do with people like John Major," he said.

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"Secondly it's an absurd suggestion as it stands because all that would happen is that the UK would set up any positive result in the first referendum to make sure the independence side lost in the second.

"We would vote for independence and then during the negotiations they would do all that was possible to ensure Scotland would get a rotten deal so voters would turn it down in the subsequent ballot. Something like this is singularly not going to happen."

He added: "The Scottish people will have the next referendum determined by a positive vote by the Scottish people and then agreed by both governments. It will have absolutely nothing to do with former Prime Ministers who have nothing to contribute in this debate and discussion."

Wishart had been earlier wary of plans for a confirmatory EU referendum abstaining on the issue in the Commons when the SNP voted in favour.

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He said at the time backing the proposal could have implications for what could happen in the event of a second independence referendum.

Back in 2018 he argued such a move could make it more difficult to resist calls for a similar confirmatory ballot in Scotland if the SNP were to win another referendum on independence.

Previously First Minister Nicola Sturgeon had said her party's MPs would "undoubtedly" back a public vote on the final deal for leaving the EU if given the option.

The First Minister has also indicated she would seek a guarantee or "double lock" for such a ballot, for example requiring the support of all four UK nations before Britain could leave the EU.

Writing in The National, in 2018 Wishart said: "To say that we will sign up to a referendum without any guarantee that our Scottish national voice will be at least acknowledged is little more than an open invitation to have our national view ignored and disrespected all over again. By enthusiastically buying into this confirmatory vote for an EU referendum, we weaken our hand in resisting Unionist calls for a second vote on a successful indyref.

"And if they were successful in using this precedent against us, unreconciled Unionists would be working non-stop from the day after the referendum to ensure that a successful outcome would be overturned.

"Every apparatus of state would be deployed and they would ensure that the worst possible 'deal' would be offered to the Scottish people in the hope that their Union could be rescued."

He added: "We could be presenting all sorts of risks to a future independence referendum for nothing."

In a speech delivered at the Middle Temple’s 2020 Lecture Series, Sir John said on Monday: “In law, the Scots require the approval of the Westminster Government before they can legally hold a new independence referendum.

“But refusing one might help the separatist case, by adding to the list of grievances the Scottish National Party exploit with such skill.

“The choice for the UK Government is either to agree the referendum can take place – or to refuse to permit it.

“Both options come with great risk. But the lessons of Brexit may offer a way ahead. The Westminster Government could agree for an independence referendum to take place, on the basis of two referenda.

"The first to vote upon the principle of negotiations, and the second upon the outcome of them. The purpose of the second referendum would be that Scottish electors would know what they were voting for, and be able to compare it to what they now have.

"This did not happen with Brexit: had it done so, there may have been no Brexit."

Scottish Secretary Alister Jack has recently again ruled out another referendum taking place for at least another generation.

A series of polls this year have shown an increase in support for independence.