Schools and nurseries across Scotland could be forced to close next month as teaching support staff are set to strike in a pay dispute.
Cleaning and waste-disposal workers have been staging a walk-out in Edinburgh since 18 August.
Litter has been piling up on the streets of the city as a result of the strikes, timed to coincide with the popular Edinburgh festivals.
Waste workers in 13 other local authorities, including Glasgow, Dundee and Aberdeen, are now also taking action.
Now unions have warned teaching staff are preparing to join the walk-out over pay next month.
“Our first wave was in Edinburgh, the second wave is waste across Scotland, our third wave is going to be schools. And it may not stop at schools, we’re in here for the long haul,” said Wendy Dunsmore, regional officer at Unite workers union.
Schools in nine council areas could be forced to close in September – at the beginning of the school year – after unions rejected a 5 per cent pay raise offer funded in part with £140 million of Scottish government cash.
Speaking to BBC Radio Scotland, Ms Dunsmore said any rise needs to “give proper recognition that there is a crisis out there for low-paid workers.“
“Our members are being offered on average of £900. That’s less than half of what is being offered elsewhere.
“Now a Tory government is offering our workers down south nearly £2,000, I don’t think it’s a bad ask for the Scottish government to at least match that.”
“We’re looking for a winter of discontent, even though we’re just approaching autumn,” she added.
Unions Unison and the GMB have said their members will walk out between 6, 7 and 8 September, which could see schools, early years centres and nurseries disrupted in Aberdeenshire, East Renfrewshire, Glasgow City, Inverclyde, Orkney, North Lanarkshire, South Lanarkshire and Stirling.
In response to ongoing strikes, first minister Nicola Sturgeon said the Scottish Government does not have a “bottomless pit of money” to resolve issues.
Ms Dunsmore added that unions don’t want strikes, but it is up to the Scottish government to prevent them.
“There is an impact but that’s not an impact because of the workers, that’s because there is a shortage of funding to the Scottish local authorities. This lands at the Scottish Government,” she said.