Mr Murrell, who is the former chief executive of the SNP and Nicola Sturgeon’s husband, was later released without charge pending further investigation.

It is understood the party is treating him as an ordinary member as he is no longer an office holder.

Asked if Mr Murrell's SNP membership should be suspended during the police investigation, Mr Yousaf, the new First Minister, said: "I don't think so. He has of course been questioned under caution, which of course is undoubtedly serious, but I tend to work on the premise that someone is innocent until proven guilty."

He said people should wait and "see where the police investigation goes".

Mr Yousaf was asked about the comparison with the SNP MSP Michelle Thomson, who was suspended by the party after police launched an investigation into property deals she was involved in. This probe was later dropped.

Mr Yousaf said: "I can't comment on what happened previously. I'm the new leader of the SNP. I tend to operate on the premise that people are innocent until proven guilty and that is the case, as far as I can tell, with Peter Murrell."

The First Minister said he had had no contact with Mr Murrell or Ms Sturgeon. He said the SNP would not be paying Mr Murrell’s legal costs.

Asked why, Mr Yousaf said: “He's no longer the chief executive of the party.” He added: “I'll be castigated, I'm sure, if we pay his legal fees and castigated if we don't pay his legal fees. So we've taken a decision as a party not to pay those legal fees given he's no longer the chief executive of the party, I think that's pretty reasonable.”

Humza Yousaf defends decision not to suspend Peter Murrell's SNP membership