Michael Russell, the SNP MSP for Argyll and Bute and the Cabinet Secretary for Education and Lifelong Learning, pointed the finger at independent councillor Dick Walsh and Liberal Democrat councillor Ellen Morton – the leader and depute leader of Argyll and Bute Council – for what he call a period of ‘instability’ at the council.

However, Cllr Walsh and Cllr Morton, who took up their positions a year ago, say other political parties are working together, while any party alternation remains within the SNP.

Mr Russell’s comments followed the news that SNP councillor John Semple, of South Kintyre, stood down on the day of the referendum ‘for personal reasons’. As a result the fourth Argyll and Bute Council by-election in just six months is set to take place – at a combined cost of at least £132,000.

Mr Semple’s departure also means only six SNP councillors remain – a drop from 13 following the local election in 2012. Three members have stepped down while others have altered their political alliance.

This is in contrast to the party’s popularity nationally, with more than 22,000 people signing up to join the SNP in the days following the referendum – boosting it into the position of the UK’s third biggest party.

Helensburgh and Lomond South councillor Richard Trail said the SNP is still the largest single political party on the council.

Cllr Trail said: “The long tradition of independent councillors casts a long shadow. The lack of cohesion of the groupings makes it very difficult to maintain an effective administration. The membership of the groups changes regularly as members flit from group to group.

“Their inability to accept collective responsibility and group discipline leads to a council which faces continual problems in taking difficult decisions.” Mr Russell said ‘something is clearly wrong’ and it has affected all parties and groupings.

He added: “The council is going through a period of extraordinary instability with further resignations from groups, realignments and resignations.

“The most common complaint I hear is of the leadership style of Dick Walsh and Ellen Morton which excludes participation in decision making by any other councillor and allows officials untrammelled power.” Mr Russell also referred to recent council scrutiny from the Accounts Commission, which he said would ‘trigger even more concern about its future’.

He added: “The Walsh/Morton administration came back in only a year ago after engineering a crisis with a pledge to settle things down. However it is now clear they were the problem, not the solution.” In response, Cllr Morton said the SNP councillors who stepped down were all members of Mr Russell’s constituency.

She also referred to the original Audit Scotland report, which included comments about external interference contributing to instability in the council, where reference was made the influence of ‘one of the local MSPs’.

Cllr Morton added that the report said there was evidence of ‘collective leadership’ in the council, in relation to the leader (from the Alliance of Independent Councillors) working well with the depute leader (from TALIG).

She said: “It is disappointing that Mr Russell finds himself unable to put party politics to the side to work constructively with the Council for the good of the people of Argyll and Bute.” Cllr Walsh added the council is ‘strong, secure and stable’.

He added: “There is a real will to work together both across the chamber and with council officers to continue delivering essential services to the people of Argyll and Bute who elected us. This is our primary focus.”