30,000 staff in every local authority in Scotland have been balloted over a pay dispute for all council workers.
Phil McGroggan, chair of Unison’s Dumfries and Galloway branch, said: "The ballot papers have already been sent to our members at schools asking them to vote for or against strike action.
"We are encouraging members working at schools and early years facilities in schools to look out for the purple envelopes, to vote and send the ballot papers back by the closing date."
He continued: "While it is only schools workers who are being balloted at the moment their action will be in support of all council workers.
"We all deserve a decent pay rise given the increase in the cost of living and the decline in real terms of local government wage levels in recent years."
Unison previously turned down COSLA's pay offer with members overwhelmingly rejecting it by 87%. 90% of those who rejected the offer also voted in favour of taking some industrial action.
Unison Scotland head of local government, Johanna Baxter, said: "COSLA’s offer falls short of Unison’s pay claim, it also less than the offer made to the lowest paid local government staff south of the border.
"And it would be a real-terms pay cut during the cost of living crisis.
"Despite efforts to move negotiations along, we’re now at an impasse. COSLA has refused to improve its pay offer, which UNISON members overwhelmingly rejected.
"It also says it doesn’t have the cash to offer more but is also refusing to ask the Scottish government for additional funding.
"Council and school staff are fed up. All school staff should look out for their ballots, which will arrive in purple envelopes, vote and post back as soon as possible."
A Cosla spokesman said the "strong offer" raises the local government living wage by 99p to £11.84 per hour.
He said: "The reality of the situation is that as employers, council leaders have made a strong offer to the workforce. A strong offer which clearly illustrates the value councils place on their workforce, and it compares well to other sectors.
"It recognises the cost-of-living pressures on our workforce and, critically, it seeks to protect jobs and services.
"While the offer value in-year is 5.5%, the average uplift on salaries going into the next financial year is 7%. Those on the Scottish local government living wage would get 9.12% and those at higher grades, where councils are experiencing severe recruitment challenges, would see 6.05%.
"It is an offer which recognises both the vital role of the people who deliver our essential services across councils every day and the value that we, as employers, place on them.
"Crucially, it also raises the Scottish local government living wage by 99p to £11.84 per hour and sets out a commitment to work with our trade unions to develop a road map to #15 per hour in a way that protects our workforce and services we deliver."
A Scottish Government spokesperson said: "Local government pay negotiations are a matter for local authorities as employers and unions.
"The Scottish Government and Cosla have committed to respect this negotiating arrangement as part of the Verity House Agreement.
"Despite UK Government cuts, the Scottish Government has provided a further £155 million to support a meaningful pay rise for local government workers, which has been taken into account in the pay offer already made by Cosla.
"The Scottish Government urges all the parties involved to work together constructively and reach an agreement which is fair for the workforce and affordable for employers."
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