ONE of the SNP's most senior councillors is to quit politics, just months after his administration resigned en masse while he was on holiday.

Willie Gibson, until recently head of North Ayrshire Council and the SNP's leader on local government umbrella body Cosla, said the decision by his colleagues to resign "didn't help" when considering his political future, suggesting he even considered quitting the party.

The SNP stood itself down after Nicola Sturgeon's father Robin failed to win a local by-election, leading to it losing its majority on the council and claims Labour would move to oust the First Minister's mother Joan from her position as North Ayrshire's Provost.

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The move comes barely a month after Mrs Sturgeon announced she would leave frontline politics after two terms as a councillor, last summer's turbulence cited as a factor in her decision.

Mr Gibson said being in opposition, which would have led to a major loss of salary, had "been a nightmare" and made clear he was opposed to last August's decision to quit. The saga had unfolded when the former teacher was at his holiday home in Italy.

It also led to him having to give up his post at Cosla, where insiders have expressed surprise at his decision.

Sources say the episode had left Mr Gibson badly bruised, with the decision to exit frontline politics now likely to open the door to Mr Sturgeon to become local SNP leader if elected on the second time of asking.

Mr Gibson said: “Being in opposition has been a nightmare for me. It's not the way I would have wanted to move and I think that is pretty obvious. I was on holiday at the time and my thoughts were to wait and see, give it time and wait until the next election and have time to speak to people.

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“My original thoughts were 'Why would you do something quickly?' and that was the proposal I suggested and I wouldn't have wanted to give up. "We had so many good things happening, why would I want to give it up?

“I'm not suggesting anyone did want to give it up but I wanted to have the time to negotiate and see how things would go but the group took a different route and I had to make a decision at that point 'Do I stick with it? Do I stick with the party?' and that's the decision I took.

“It didn't help. I would say to go from leader of the council and working basically seven days a week and working with senior officers and working at Cosla with government ministers at that level to suddenly being in opposition and not only that, to be so close to the next election and watch all the fruits of our labour being claimed by a party who didn't set any of it, I found it very difficult and it certainly didn't help."

In an extensive interview with The Herald's sister paper, the Ardrossan and Saltcoats Herald, Mr Gibson said that his interest in local affairs superceded that of national politics and that such priorities "cause conflict all over Scotland". He also said he had faced criticism for not defending the Scottish Government enough.

Mr Gibson also said that while he believed the SNP would form the next administration in North Ayrshire they would not secure an overall majority.

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He said: “I think the SNP will gain seats all over Scotland and will probably gain Glasgow but I don't know that they will have a majority in North Ayrshire, I would predict they will lead North Ayrshire but to get a majority in the local government system is very difficult but they are putting up two candidates in every ward which, if things go well, will give them the potential to have a majority."

An SNP spokesman said: “Cllr Gibson has been a passionate and hard-working representative for North Ayrshire over the past decade and his contribution will be missed by his colleagues."