The Scottish National Party's treasurer Colin Beattie said on Wednesday he would be "stepping back" from the role until a police investigation into the party's finances was concluded.
Beattie was arrested and questioned by Police Scotland on Tuesday, before later being released without charge pending further investigation.
"This afternoon I informed the party leader that I will be stepping back from my role as SNP National Treasurer with immediate effect," Beattie said in a statement, adding that he was doing so to avoid futher distraction from the work of new party leader Humza Yousaf.
"I will continue to cooperate fully with Police Scotland's enquiries and it would be inappropriate for me to comment any further on a live case."
The police investigation is looking at what happened to more than 600,000 pounds ($750,000) raised by Scottish independence campaigners in 2017, which was supposed to have been ring-fenced but may have been used for other purposes.
Yousaf, who replaced Nicola Sturgeon as the SNP's leader last month and has seen the first few weeks of his tenure dominated by questions about the party's credibility, said a new treasurer would be appointed as soon as possible.
"I want to offer my thanks to Colin. I know that his decision to step back from the role of SNP National Treasurer will not have been an easy one, but he has done so in the best interest of the party," Yousaf said on Twitter.
Peter Murrell, Sturgeon's husband and the party's former chief executive, was also arrested and then released without charge earlier this month as part of the party funding investigation.
(Reporting by Andrew MacAskill, writing by Kylie MacLellan)
