A potentially unpalatable plan to close Police Scotland's spiralling £25 million shortfall will not be rushed and the forthcoming Scottish election will play no part in its publication, according to an SNP councillor tasked with overseeing scrutiny of the police budget.

Graham Houston, chair of the Scottish Police Authority's (SPA) finance and investment committee and an SNP veteran, said the SPA's scrutiny "can't be governed by a magical date that we have to get manifestos out by".

Discussions about the available options to close the budget gap are still being held behind closed doors amid concerns that "some will be more palatable than others", he said.

The SPA is focussed on getting the best plan for Police Scotland and "what the politicians want to do, that's entirely up to them", he added.

Police Scotland is currently constrained from cutting its biggest budget line - police officer costs which account for nine-tenths of spending - by the SNP's manifesto commitment to maintain officer numbers above 17,234.

In August, outgoing Chief Constable Sir Stephen House questioned whether some of the options to close the gap - then publicly stated to be £11 million - would be "politically acceptable".

Last month, Police Scotland revealed the gap had more than doubled to £25 million and warned quick savings cannot be achieved without "further rationalisation".

The SPA hopes to have a plan in place by its next meeting on December 16, but negotiations continue over what should be made public and it is unclear whether choices will be published ahead of the dissolution of the Scottish Parliament on March 24 next year.

The SPA's performance and strategy team is already scrutinising its workforce balance to inform funding negotiations with the next Scottish Government, with internal and external discussions and research into other sectors.

The scale of the problem was touched upon at today's committee meeting, as board members publicly debated a £40 variance in one-bedroom officer "hostel" rents in the islands and a £500 saving by closing a supermarket police counter in Inverkip, while discussion over the £25 million budget gap was reserved for private session.

Speaking after the public session, Mr Houston said: "These are not easy decisions that they have to take.

"Getting a plan together and rushing it out is really of no use to us. This is a plan which, if implemented, does the job that it's expected to and close that gap.

"There needs to be that range of suggestions, some of which will be more palatable than others and that is a decision for the board.

"We're charged with making sure that it is right for Police Scotland, and that's our job.

"What the Scottish Government want to do, and what the politicians want to do, that's entirely up to them.

"We can't be governed by a magical date that we have to get manifestos out by. That is not featuring in our discussions and our thinking.

"We are faced with the challenge of a £25 million gap in our budget and we have to close that gap. That is the focus.

"In saying there is a whole range of options, and that some might be easier than others, I am talking about our accountability to the public and the people of Scotland about what we might need to do and how that impacts on the delivery of an effective police service."

An SPA spokeswoman said: "Detailed work to identify savings and mitigate against the projected budget overspend in the current financial year is ongoing.

"Members of the SPA's dedicated finance and investment committee considered Police Scotland's progress on this work during their meeting today and expect further updates in the coming weeks before the full SPA meets again in December.

"The SPA is also firmly focussed on the need to have a clear plan for meeting the further financial challenges anticipated in 2016-17 and beyond.

"SPA members continue to seek evidence and further assurance from Police Scotland that everything possible is being done to reduce the forecast overspend."

Scottish Labour justice spokesman Graeme Pearson said: "It's interesting to see the SPA finally stand up to the SNP government - for too long they have been a lapdog rather than a watchdog. The timing of it is highly questionable, however.

"After a summer which has seen the reputations of police staff and officers dragged through the mud, we are now seeing an SNP councillor threaten to kick transparency about the police budget into the long grass until after the next election.

"It is clearer than ever that we need to have a transparent police service. When the Scottish public go to the polls next May they must have a clear sense of the long-term finance arrangements for Police Scotland. Anything less would be completely unacceptable."