ScotRail workers could be balloted for strike action after a breakdown in talks aimed at resolving a pay dispute.
An offer of 5% made by the rail operator was rejected by members of the Rail, Maritime and Transport (RMT) union was rejected last week.
The terms of the deal were rejected due to a clause over the use of new technology.
Further talks were held this week, but no agreement was reached between union leaders and ScotRail.
Railway services have already been severely reduced due to industrial action being taken by National Rail workers.
RMT Scotland organiser Mick Hogg explained that the latest offer by ScotRail “comes nowhere near” the aspirations of members in the face of the cost of living crisis.
“The talks broke down because the improved offer that was made by ScotRail does not meet our members’ aspirations. It comes nowhere near in the cost of living crisis,” he said.
“It was made absolutely crystal clear to ScotRail that failure to make an acceptable offer would lead to a ballot for industrial action.”
Phil Campbell, ScotRail head of customer operations, insisted that the offer made is a “strong one”.
“We met with RMT representatives to discuss the next steps as we seek to resolve this dispute,” Campbell said.
“It is very disappointing that the RMT may hold a ballot for industrial action, despite ScotRail making a further improved offer.
“The offer made to our staff is a strong one and recognises the cost of living challenges faced by families across the country as well as delivering good value for the taxpayer. ”