Nicola Sturgeon has denied her party is in crisis after concerns were raised about the integrity of the race to succeed her, claiming she has “100% confidence” in the process.

The campaigns of leadership candidates Kate Forbes and Ash Regan have called for an independent auditor to oversee the election, citing a need for transparency.

Asked by journalists after First Minister’s Questions on Thursday if the SNP is “in crisis”, Ms Sturgeon said: “No, it is not.

“My party is having a democratic leadership election – growing pains for any organisation can be painful, but they are important.

“I think it’s incumbent for the three candidates standing to succeed me that they remember the task is to retain the trust of the Scottish people that we have won consistently over, not just the eight years of my leadership, but consistently since 2007.”

Asked if there should be an independent auditor appointed, the First Minister said the company currently undertaking the election process – Southampton-based Mi-Voice – is independent and has been used in selection processes for three SNP deputy leadership elections, “a range of internal elections” and for candidate selections.

Ms Sturgeon went on to say she is unclear about the allegations being made by the campaigns of Ms Forbes and Ms Regan.

“I am not absolutely clear what the specific allegations about the process are,” she said.

“This is a tried and tested process that the party has trusted for years.

“As far as I can tell, there are no specific concerns being raised, it’s a general concern, and I don’t think that general concern is justified.

“I have confidence, I have 100% confidence, in the integrity of that system.”

In a statement, an SNP spokesperson shot down the calls for an independent auditor, saying: “All three leadership candidates were successful in parliamentary selection contests using exactly the same voting system and independent ballot services firm.

“The national secretary has again confirmed all necessary safeguards are in place to protect the integrity of the ballot.”

It is understood that no-one in the SNP has access to live data from Mi-Voice, with the result to be sent to national secretary Lorna Finn after ballots close on March 27.

Ms Finn is also understood to have written to the three candidates offering a meeting on the operation of the election rules.

Also speaking to journalists after FMQs, Ms Regan was unable to give any specific examples of issues with the voting system. A senior source in her campaign last week said there were worries about votes from deceased party members or those who have allowed their membership to expire.

Addressing the use of Mi-Voice, Ms Regan said: “They are an independent company but they’re also on contract to the SNP.

“Just for the sake of increased transparency, my view is it should be a separate company that the SNP don’t have an ongoing relationship with, and we’ve also called for an independent observer, just to oversee the process.”

Asked if raising concerns without specific allegations is similar to the actions of former US president Donald Trump – who continues to cast doubt on the result of the 2020 US election – Ms Regan said: “No, I don’t think so.”

On Wednesday, Michelle Thomson – who is running the Forbes campaign – said some concerns are “based on hearsay or are from bad faith actors”, but she added: “However, others are being openly expressed by individuals within the SNP of longstanding.

“We all agree that the party must unify around any newly elected leader.

“I have asked that the SNP appoint a robust, experienced, third-party auditor of both the ballot processes and the eventual tally of the vote. This third party must have full oversight of all membership numbers, data and processes.

“This should be done without delay.”

Kirk Torrance, who is advising Ms Regan, said on Twitter: “Independent auditors will give reassurance to the SNP members and the general public that this ballot is conducted properly. This should have been the case from the outset.”

But the concerns were dismissed by fellow candidate Humza Yousaf, who hit out at the “baseless smears”.

He said on Twitter: “I have confidence in the process that uses an external third party company, a process we have used for many years.

“I am up for challenge & reform of the party, but let’s not indulge in baseless smears.”

SNP president Mike Russell tweeted that he has “full confidence” in the “external verification” of the election, adding that any allegations to the contrary “aid our enemies”.

There has also been pressure on the party to release its total membership numbers, with all three candidates calling on it to do so.

Ms Sturgeon said it is “right” the party’s ruling body considers releasing the figure, adding it is expected some time on Thursday.