In a ballot of members, Unison, the nursery nurses' union, has won a call for all-out action by a four to one majority on a 70 per cent turnout.
Local authority leaders were believed to be surprised at the strength of the vote.
A Unison spokesman, however, said there was still "a window of opportunity" for employers to reach a national deal before the union next week brings in its branches to plan a strike campaign. It must give employers seven days'
notice of any action. The union alleges that local authorities refuse to negotiate and have not made an offer at national level.
The authorities reply that any deals must be concluded locally within a national framework and point to the six councils which have already settled locally, dropping out of the 10-month dispute.
In Stirling, where agreement was reached two weeks ago, pre-five staff will see rises of up to 12 per cent backdated to last April. Salaries will now rise to more than pound;15,500 for newly qualified nursery nurses and up to pound;18,400 for more experienced staff who can double their salary and reach senior positions if they acquire extra qualifications.
Marion Henderson, the local union branch secretary, said: "If the agreement we reached in Stirling Council was made nationally, I believe this dispute would be over. It's a good respectable settlement, slightly outwith the more rigid national framework."
South Lanarkshire, Shetland, Aberdeen, Perth and Kinross and Highland are the others to end the pay saga.
Joe di Paola, Scottish organiser for Unison, said that fewer than 10 per cent of its members had settled in the six authorities, leaving a clear majority unhappy. Mr di Paola remarked that the Stirling deal appeared to be better than than the one the Convention of Scottish Local Authorities was promoting nationally.
He insisted that the employers' top line of pound;18,500 was the union's bottom line in a pay claim submitted two years ago. He believes that many staff on the top scales in authorities which have reached agreement will be paid less than the highest salary since their hours will be reduced to the school year.
Staff could end up with pound;15,000 rather than the pound;18,000 that some authorities were highlighting. The top scales were based on maximum hours and weeks in the working year, not the school year.
Authorities, however, show no signs as yet of bending to the threat of industrial action in nurseries and seem set for a long haul.
Meanwhile, the Educational Institute of Scotland called on the authorities to recognise the important role that nursery nurses play in schools.
"The authorities must act for the good of nursery education and take steps to bring this dispute to a quick conclusion by making an appropriate offer to the nursery nurses' representatives," Ronnie Smith, the union's general secretary, said.