Mr Foote, the former editor of the Daily Record, said he was resigning from the SNP after being let down by party HQ while “acting in good faith”.

He told how he issued “agreed party responses” to the media in order to rubbish a newspaper report that the SNP had suffered a loss of 30,000 members.

But this week the party admitted its membership had dropped by more than 30,000 below its previously published figure – indicating leading figures in the party wanted the collapsing membership to remain secret.

It led to an explosive row in which Mr Murrell was effectively forced from office – just a month after his wife resigned.