Video: Sturgeon's referral to ethics watchdog over Salmond case 'does not go far enough'

But both the Scottish Labour leader Richard Leonard and Jackson Carlaw, the deputy leader of the Scottish Conservatives said it should not preclude an inquiry into the whole affair.

Ms Sturgeon admits that she met her predecessor on three occasions and spoke to him twice on the phone after he was the subject of sexual harassment allegations in January, last year.

Ms Sturgeon on Thursday: "I at no stage intervened in the process".  Source: Scottish Parliament TV

Scotland's highest civil court, the Court of Session ruled on Tuesday that the handling of the allegations against the former first minster were unlawful.

Mr Leonard had accused the First Minister last week of breaching the ministerial code after she admitted at first minister’s questions and then later to reporters that she had failed to tell Scottish civil servants that Salmond had met her at her home on April 2 to tell her about the government investigation.

Mr Carlaw said the First Minister should take further action.

He said: "The First Minister says that Parliament deserves assurances about the way she and her administration handled this matter.

"The best way to do that isn’t to kick the matter into the long grass, it’s to agree to an inquiry by parliament so MSPs can find out what has gone on. The First Minister’s decision to refer herself under the Ministerial code does not change that.

"To be clear, there is no reason why such an inquiry need impact on the separate police investigation into Mr Salmond. And any attempt by the SNP to use that separate inquiry to evade legitimate questions would be quite wrong.

"Nicola Sturgeon’s handling of this matter over the last week has been absolutely abysmal. It strongly suggests that the Scottish Government is trying to hide the facts in order to save the First Minister’s skin and today's statement only adds to that impression.

"It is time for the First Minister to stop dodging and accept that finding excuses to avoid the many wider and important questions will not wash. It's time to front up."

Ms Sturgeon's referral comes as it emerged that Sturgeon's goverment is at the centre of a criminal investigation over the leak of highly sensitive allegations relating to the sexual misconduct case.

In a letter to the former First Minister’s team, the Information Commissioner’s Office (ICO) wrote that it appears an offence may have been committed over the unauthorised disclosure to a tabloid newspaper.

It was further claimed that Scotland's top civil servant Leslie Evans, who was in charge of the internal investigation into Salmond is likely to the first casualty in the fallout from the court ruling.

And Kevin Pringle, a former adviser to Sturgeon and Salmond, said the First Minister should “lead the charge” for an independent inquiry covering the conduct of ministers and officials.

Ms Sturgeon inisted that she had acted "appropriately and in good faith throughout" and was in compliance with the Ministerial Code at all times.

"However, I have reflected carefully and understand that it is also important for Parliament and the wider public to be assured of that," she said.

"I have therefore decided to refer the matter for consideration by one or both of the Independent Advisers on the Ministerial Code."

She added: "It is in the interests of the women who have complained that the ongoing police investigations are allowed to continue without any risk of prejudice. That must be the priority for everyone.

"Questions have been raised about my meetings and telephone calls with Alex Salmond during the Government's investigation into the complaints which were made.

Opposition parties had been calling for the FM to make the referral to the watchdog with Mr Carlaw describing the situation as "a shambles" during First Minister's Questions on Tuesday.

Ms Sturgeon stated that the complaints made against her predecessor could not be ignored.

She explained: "The Independent Advisers will now be consulted on their precise remit and advice will also be sought on how to ensure that there is no risk of prejudice to the ongoing police investigation. The remit will be published in due course.

"The fact remains that at the centre of this issue are two women whose complaints could not be swept under the carpet.

"Any continuing commentary about these issues at this stage - whether from myself, the Government or Mr Salmond and his representatives - would only serve to distract from, and potentially compromise, the proper consideration by the police of the subject matter of their investigations. That is something we will not do," added Ms Sturgeon.

Richard Leonard, the Scottish Labour leader, said the FM had "done the right thing" in referring herself under the Ministerial Code and called for a full inquiry.

"Transparency is now absolutely essential in order for the public to have confidence in the First Minister and the Scottish Government.

"That is why we should also see a full, public parliamentary inquiry in to what exactly has happened - and I look forward to working constructively with members from other parties this week in order to secure that."

He said it was now essential that Holyrood was given the power to fully review the outcome of the investigation into whether or not Ms Sturgeon had broken the Ministerial Code.

"Throughout this process it is essential to remember that at the centre of all of this are two courageous women, who put their faith in a system that has badly let them down and we must never lose sight of that, by safeguarding the duty of care to them and their access to justice," stressed Mr Leonard.