Its long-standing accountants Johnston Carmichael, which has worked with the party for more than a decade, said the decision was made after it reviewed its client portfolio.

But the resignation will raise eyebrows as it comes during a police probe into the SNP’s finances and alleged fraudulent activity.

The SNP will need to have its accounts independently audited due to laws meaning any party that brings in or spends more than £250,000 needs to show this in a report to the Electoral Commission.

It has until July 7 to present its accounts or face possible sanctions. This is in accordance with the Political Parties, Elections and Referendum Act 2000.

The resignation comes just days after police arrested former chief executive Mr Murrell and searched the home he shares with ex-First Minister Nicola Sturgeon. He was questioned under caution for 12 hours before being released without charge on Wednesday.

A spokesperson for the SNP said the party was in the process of finding a replacement firm. They added: “We can confirm that Johnston Carmichael will not be providing audit services to the SNP this year.

“The national treasurer is undertaking a tendering process for alternative provision, and we have advised the Electoral Commission of that position”.

If no auditor is appointed, or a report is unavailable, the Electoral Commission has the power to appoint its own firm of auditors to look at the accounts.

The party’s last published accounts for 2021 were revealed on August 2022 which showed that it had operated at a loss for the year. Its total income was £4,510,460, total expenditure was £5,262,032, assets were £1,630,454 and liabilities were £1,055,689.

This new revelation comes amid speculation surrounding the financial health of the SNP. Along with the home of Mr Murrell, the party’s HQ in Edinburgh was also raided by the police.

New First Minister Humza Yousaf said that he had asked for a review of the finances when he took over from Ms Sturgeon and that his party had “fully co-operated” with police and will continue to do so.

He also claimed that he had nothing to do with the governance but that it was “not as it should be” as he vowed he would be more transparent than his predecessors.

Police are investigating whether or not the SNP fraudulently spent £600k of money which was meant to be ring-fenced for an independence referendum.

Scottish Labour deputy leader Jackie Baillie, right,  said: “Yesterday, Humza Yousaf attempted to distance himself from the legacy of Peter Murrell – today we need to know what the current first minister plans to do to get the SNP’s house in order. Sunlight is the best disinfectant – we need transparency and openness from the SNP now.”

Scottish Tory constitution spokesman Donald Cameron urged the party to be “fully transparent” about why their auditors decided to quit.

He said: “The public are sick of the SNP shrouding matters relating to their finances behind a wall of secrecy, and senior figures – including Humza Yousaf and Nicola Sturgeon – must be upfront about this situation.”

Humza Yousaf has launched a recruitment drive to bring in a taxpayer-funded £90,000 spin doctor in a bid to shore up his leaky administration which has lurched from disaster to disaster.

The First Minister has had to deal with numerous tough issues in his first fortnight in the job, including a row over his cabinet and the arrest of the former SNP chief executive Peter Murrell.

In a bid to head off these challenges and drive some distance between him and Nicola Sturgeon, despite being the “continuity” candidate, he is recruiting externally for the role.

He is looking to bring in a head of communications, who is usually the first port of call for journalists asking questions of the First Minister specifically.

Previously the role was filled by Stuart Nicolson who is a former Daily Mail reporter and joined the government in 2008. He had been Ms Sturgeon’s appointment in the job.

But the Herald revealed that he was now leaving alongside former top adviser Liz Lloyd, who announced her departure last month, and net zero adviser John McFarlane.

A source told them that the next head of communications would be an external appointment and was part of the “new start” that Mr Yousaf wanted to bring in.

They said: “I don’t think anyone internal will be appointed. Someone from outside will be brought in and made a special adviser in Stuart’s old role.”

One of their key roles involves hosting a weekly media briefing after First Minister Questions where they would face tough questions from journalists about the prior week and government policies.

It is a job which Mr Yousaf has free rein to pick at his pleasure because they would serve him meaning there is no need for a formal appointment process.

The salary on offer is up to £90,000 but will be a tough role to fill amid chaos within the SNP and the Scottish Government. An uprising of nationalist MSPs has been hinted at due to concerns about numerous policies, including gender reforms and the deposit return scheme.

There is also the ongoing police probe into the SNP finances which could engulf Mr Yousaf if his predecessor Ms Sturgeon is spoke to by cops like her husband was.

An early test for the First Minister will also be the likely by-election in Rutherglen where former SNP MP Margaret Ferrier, left, could face a recall petition after she broke Covid rules.

It is another key role which Mr Yousaf will have to fill as he is also looking at bringing in a new chief executive for the party following Mr Murrell’s resignation, and also a head of communications at Holyrood after Murray Foote quit, both involved in the misleading of journalists around the SNP’s membership figures.

Those two jobs will help to shape the future of the nationalists who have been in turmoil ever since Ms Sturgeon shockingly resigned suddenly in February.

Mr Yousaf confirmed on Thursday that the process to find a new chief executive would be “open” in a bid to make the party more transparent following rows over their finance and governance.