LIZ Truss’s election as Conservative leader would be “invalid” if she followed the same rules as she reportedly plans to force on the Scottish electorate, the First Minister has said.

It comes after Truss – who will be officially appointed prime minister on Tuesday – beat Rishi Sunak in a poll of Tory Party members to win the rights to take the keys to No 10.

Truss beat her final opponent in the race by 81,326 votes to 60,399 – giving her a majority of 57% against 43% for Sunak.

However, the referendum bill which the new Tory leader is reportedly plotting would see the Yes side need 50%+1 of the entire electorate to win indyref2 – not only 50%+1 of those who voted.

This is an extremely high bar, and one which Truss would have failed to pass in her bid to be elected Tory leader.

The foreign secretary’s 81,326 votes represent just 47% of the electorate in the leadership ballot.

There were 172,437 Tory Party members eligible to vote, although just 82.6% did so.

As such, Truss would have failed to win the race to be the UK’s next prime minister if her own proposed rules had been in place.

Commenting on the figures, First Minister Nicola Sturgeon tweeted: “47% of the total electorate – worth noting that if the principles of her mooted new referendum law applied here, her election would be invalid.”

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Truss will further face a battle to unite the Tory Party after her share of the membership vote was smaller than any of her predecessors as Conservative leader.

Boris Johnson’s victory in the same contest in 2019 was far more decisive, picking up 66% of votes compared to Jeremy Hunt’s 34%.

David Cameron managed an even bigger share in 2005, winning 68% of votes to David Davis’s 32%.

Truss also fell short of the total secured by Iain Duncan Smith in 2001, who picked up 61% of votes versus Ken Clarke’s 39%.

The National:

Her election was also the first time since 2001 when the candidate with the strongest support among MPs did not win the membership ballot. Sunak had the support of 137 MPs before the final round of voting, while Truss had 113.

The SNP’s longest serving MP, Pete Wishart, said: "The fact Liz Truss failed to win the support of 50% of eligible Conservative party members shows just how absurd and undemocratic Tory proposals to rig the rules of an independence referendum are – and it leaves the Tory government with egg all over its face.

"If the same rules were applied to the Tory leadership election, neither candidate would have won, the vote would be null and void, and it would have to be re-run all over again.

"Westminster attempts to deny democracy and rewrite the rules are doomed to fail and will only backfire, increasing support for independence even further."

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While the plans to change the rules around referendums have been attacked by the SNP, a senior government ally of Truss previously defended the proposals.

They said: “After all, the SNP said after the 2014 referendum that they would not seek another [independence vote] until polls consistently showed more than 60 per cent of the public would vote to leave the UK.

“In order to achieve independence it would not be unreasonable for the Yes side to demonstrate that it was the settled will of the Scottish people like in the 1997 devolution referendum where there was a three to one majority in favour of a Scottish Parliament.”