Trade unions representing local government workers have sent out a joint letter demanding an improved pay offer to prevent strike action.

Unison, Unite and the GMB have written to every Scottish council leader urging them to up their offer of a 3% increase for staff or risk "widespread industrial action across the local government workforce".

Members, who rejected the recent the pay offer, will demonstrate outside Friday's meeting of Cosla leaders in Edinburgh and say there will be strikes in the new year if the offer is not improved.

The letter to the 32 council leaders sets out the unions' key concerns and states: "There is now a very real possibility of widespread industrial action across the local government workforce unless you take measures to improve the current offer."

Drew Duffy, GMB senior organiser, said: "Cosla and the Scottish Government are running out of time to do more for the lowest paid in local government.

"Our members are very clear that they are prepared to move to industrial action in their fight for a better offer and after a decade of cuts to their pay and conditions, no one should be surprised.

"How the employer-side responds over the coming days will be a reflection of how they value workers on the front-line of our vital local services - and it will also shape the unions' next steps."

A Scottish Government spokesman said: "We value and recognise the contribution of all council staff.

"However, pay for local government employees, other than teachers, is negotiated between the unions and COSLA and the Scottish Government is not part of that process.

"Despite continued UK Government real terms cuts to Scotland's resource budget, we have treated local government very fairly. "