Nicola Sturgeon has said she will likely be “haunted” for the rest of her life after an error by the Scottish Government “let down” two women who brought harassment complaints against her predecessor Alex Salmond

The First Minister was speaking as she was accused of racking up an additional six-figure sum in lawyers’ costs, as her administration continued to fight the legal challenge Mr Salmond mounted over the way those complaints were handled.

Legal advice, which ministers have taken the unusual step of making public, shows the Scottish Government’s lawyers had “mounting concerns”, she conceded.

Scottish Conservative Holyrood leader Ruth Davidson noted the papers show that on December 17 2018, the Government’s senior lawyer Roddy Dunlop QC had “warned the First Minister personally against ‘ploughing on regardless’ because of a large expenses bill which would inevitably rise”.

The Scottish Government conceded the judicial review almost a month later on January 8 2019, with Mr Salmond awarded a pay-out of more than £500,000 at the Court of Session in Edinburgh.

That was after the court ruled the Government had acted “unlawfully” in the way it dealt with the complaints, noting the investigating officer appointed had already had prior contact with the women involved.

Ms Davidson said: “We have since learned that from the moment Roddy Dunlop wrote that note on December 17 to the time when the Government finally conceded, the bill exceeded £100,000.

“Perhaps even £200,000, but we don’t know for sure because the Government won’t tell us their side of the bill.”

Ms Sturgeon told MSPs the advice from the Government’s law officers as late as December 11 2018 was that ministers should “continue to defend the case” and there were “credible arguments” to be made in all areas, “including the appointment of the investigating officer, which was the key area of problem for us”.

But she accepted a mistake was made “in the application of this procedure”.

She added this became “fully understood during the process of the judicial review”, and this was “what ultimately meant we couldn’t defend the judicial review”.

She accepted a “different first minister may have reached different judgments” about whether to press on with the case.

Ms Sturgeon said: “It is undeniably the case the Government made mistakes here, which I, we, are determined to learn from.

“I will be haunted for probably the rest of my life about the way in which the Government through an error, an error made in good faith but nevertheless an error, let down those women.

“I have apologised for that. I wasn’t involved in the investigation so I wasn’t aware of the error at the time, but as head of the Scottish Government I take, and I feel, responsibility for that.”

She told Ms Davidson a review of the Government’s complaints handling procedure, being carried out by Laura Dunlop QC, would be made public.

But she denied a suggestion from the Tory that ministers already have Ms Dunlop’s report.

During First Minister’s Questions, Ms Davidson said: “Our clear understanding is that Ms Dunlop has reported, in writing, back to the Scottish Government on her work.

Ms Sturgeon told her: “I have not seen Laura Dunlop’s review, it will be published and it will be published in early course once we have seen it.

“I want everything about this to be open and transparent, because I do want to learn lessons.”

A spokesman for the First Minister subsequently confirmed that Ms Dunlop’s review had been received by the government on Thursday morning, but said that Ms Sturgeon was unaware of that until after FMQs had concluded.