NICOLA Sturgeon told John Swinney to “be ready” to replace her in case she was found to have lied to parliament, despite repeatedly insisting she told the truth, it has been claimed.

The First Minister’s private concern about being found guilty of a resignation-level breach of the Scottish Ministerial Code was in contrast to her public protestations of innocence.

The claim is made in Break-Up, a new book about the bitter rift between Ms Sturgeon and her predecessor Alex Salmond, written by journalists David Clegg and Kieran Andrews.

It says Ms Sturgeon made contingency plans for her resignation earlier this year as she awaited the outcome of an investigation into her conduct.

At the time, she had been accused by Mr Salmond of misleading Holyrood about a meeting the pair had on 2 April 2018 about a Scottish Government misconduct probe into him.

Ms Sturgeon told parliament she did not know what Mr Salmond wanted to discuss, and was shocked when he told her he was under investigation by her officials. 

But Ms Sturgeon later admitted that one of Mr Salmond’s former aides had told her four days before that Mr Salmond was under investigation, claiming she had “forgotten” about it. 

Mr Salmond claimed Ms Sturgeon misled parliament about her advance knowledge of the meeting, and therefore broke the ministerial code - a resignation matter at Holyrood.

Mr Salmond ultimately had the flawed Government investigation set aside in a court.

While insisting she had told parliament the truth, Ms Sturgeon asked the independent adviser on the code, James Hamilton QC, to investigate the matter.

On March 18, MSPs examining the bungled investigation concluded, on a split vote, that Ms Sturgeon had misled parliament about the nature of the meeting, and breached the code.

If Mr Hamilton had agreed, it would have spelled the end for the First Minister.

But on March 21, Mr Hamilton reported Ms Sturgeon did not breach the ministerial code, although he added it was for MSPs “to decide whether they were in fact misled".

Ms Sturgeon said afterwards that she would have resigned had Mr Hamilton concluded there had been a ministerial code breach.

The new book claims the First Minister went further than that, making plans for a succession.

It says that in the days leading up to Mr Hamilton’s report being published, Ms Sturgeon took counsel with her deputy and other close allies.

“These included Swinney, who she told to be ‘be ready’ for what might come at the start of the week. In effect, she was preparing him to step up and take over as leader of the government and try to reunite a fractured SNP just weeks before a crucial Holyrood election.

“Her popularity had soared back to levels not seen since the 2015 election campaign as the public showed their approval of her daily coronavirus press briefings, but it was Sturgeon’s view that the office of first minister was more important than her personal survival, and she would have resigned if Hamilton had been overtly critical or found that she had broken the rules.”

The book quoted a long-standing aide as saying: “For those 72 hours - from the Thursday night until five minutes past midnight on Monday [when the report was issued] - things were up in the air because we didn’t know what was going to happen.” 

As deputy FM, Mr Swinney would automatically have replaced Ms Sturgeon as acting First Minister had she resigned.

Having been SNP leader from 2000 to 2004, Mr Swinney was also seen as a potential long-term successor, and filling the FM's role in an acting role would have helped.

Other senior nationalists were also being mooted as possible replacements, including cabinet secretaries Humza Yousaf and Kate Forbes.