ALISTER Jack has said an independence referendum held without the permission of Westminster would be illegal.

The SNP released an 11-point plan last week stating they would hold another vote if a pro-independence majority of MSPs was returned in May's Holyrood elections, whether a Section 30 order granting it from London was forthcoming or not.

The document, put together by Constitution Secretary Michael Russell, would effectively dare the UK Government to challenge another referendum in court.

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However, the Scottish Secretary told the BBC today another vote without express permission would be illegal.

He said: "I'm afraid the constitution is a reserved matter, it would be an illegal referendum, let's be clear about that."

The Tory Cabinet minister said it was "not the time" for another vote on the constitution in Scotland, reiterating that senior figures in the Yes campaign and its own white paper said the vote was "once in a generation".

He added: "We can't go into a process of 'neverendums' until eventually they get one that they win, that's not what responsible government is about.

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"We had a referendum in 2014, we're now in a global pandemic, we're going to have double-dip recession the way things are going.

"It's about recovering our economy as one United Kingdom, pulling together, doing the trade deals we want to do, improving Scotland's economy and rebuilding it as quickly as we can, and after we've saved people's lives with this vaccine, then saving their livelihoods."

Earlier this month Boris Johnson said there shouldn't be another independence until 2055, but last week refused to say whether he would pursue a legal challenge to a Holyrood bid to hold a new vote.

He has repeatedly ruled out agreeing to a new vote and is also being advised not to amid increasing support for independence.

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Some 20 successive polls have recorded a majority in favour of independence with two surveys giving record 58% support.

Amid Johnson's refusal Nicola Sturgeon has backed an alternative way forward – daring Johnson to mount a legal challenge to Holyrood legislation to hold a new vote.

The First Minister told an event on Thursday: “For arguments sake, say he does and he just decide to dig his heels in.

"Well this question of does the Scottish independence referendum need the consent of Westminster or could the Scottish Parliament legislate itself, that has never been tested in courts and I hope we never get to the point where it would have to be tested in the courts.

The National:

Yes marchers in Edinburgh before the pandemic. Some 20 successive polls have recorded a majority in favour independence.    Photo Colin Mearns

“Back in 2014 at the time Alex Salmond and David Cameron decided to put that question beyond doubt and come to an agreement and that’s the precedent we should use if people in Scotland vote for a party that is proposing a referendum, but [if that route is not open] ... we would implement the mandate and if Boris Johnson wanted to say we didn’t have the legal authority then he would have to test that in court.

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“He would have to go to court to stand in the way of the democratic wishes of the Scottish people. All I would say to that Boris is ‘good luck.’ It’s not a position any self-respecting democrat ever contemplates finding themselves in.”

Responding to Jack's intervention today, the SNP depute leader Keith Brown said: "The Tories sound more rattled by the day and it's clear they are completely out of ideas and excuses.

"Trying to block a democratic mandate is an indefensible and untenable position - the bottom line is the Tories are panicking as they run scared of a referendum they fear they will lose.

"It's not for Alister Jack, or his boss Boris Johnson, to deny the people of Scotland the chance to determine their own future.

"That choice belongs to the people of Scotland and any Trump-like attempt to deny that would be utterly undemocratic - and would not hold."

Jack's comments come just days after the Prime Minister tried to tout the strength of the Union on a visit to Scotland.

When asked about the visit, Jack said it was essential, adding it was "morale boosting".

"In any battle, the general should go to the front line and hear from those people, those troops – who are fighting in this case the virus – exactly the issues they're facing," he said.

"It's morale boosting what he does, he thanked the troops who were rolling out the vaccine centres ... it's important to talk to people, to thank them, to hear what issues they're facing."

Scottish Tory leader Douglas Ross last week called on voters to boycott a second independence referendum which had not received the UK Government's consent.