The employees affected, who include plumbers, electricians and other maintenance workers, number 222 in Dundee, 283 in Fife, 21 in Perth and Kinross and three in Angus.

The union has accused Scotland’s 32 local authorities of refusing to treat craft workers equally, leaving them working longer hours and facing a lower pay increase.

Scottish local authority craft workers currently work a 39-hour week, while craft workers in the rest of the UK work 37 hours.

Five years ago other local authority workers in Scotland had their hours reduced from 39 to 37 without any loss of pay.

Unite also rejected a 2.45% pay offer as other workers in Scottish local authorities received a higher pay increase.

Unite national officer John Allot said, “We are demanding Scottish local authorities put an end to the unequal treatment of our members.

“Local authority craft workers currently work alongside other colleagues who work fewer hours and received a higher pay deal this year.

“This is totally unacceptable and the union has no choice but to ballot its members for strike action because of this unequal treatment.”