CARE workers in Glasgow are to ballot for industrial action as part of an agreement to end a series of wildcat strikes.

Around 100 city council staff working with the homeless took part in the unofficial industrial action following the suspension of a colleague and amid ongoing grievances over workloads.

All those involved returned to work at lunchtime yesterday after up to 400 workers were threatened with the sack if they took part in any further wildcat action.

Part of the deal has also involved the return to work of the suspended worker, with no further action to be taken against her.

It comes as Stirling Council denied taking on any outside labour to deal with the backlog of work caused by ongoing strike action across the authority.

The major unions are taking targeted action within the council in an ongoing row over claims they have been offered a 0.5% pay cut and been asked to work an extra hour a week.

Unions say the cut amounts to considerably more in real terms.

It is understood that the three main unions, Unison, GMB and Unite, are planning a campaign against allegations that casual and temporary workers are being brought in.

Unions claim this flies in the face of agreements struck with the umbrella body for Scotland's 32 local authorities over the handling of industrial relations.

A council spokeswoman initially said around 30 casual staff had been taken on by Stirling's waste services, but later said no workers had been taken on.

Last night, Unison said its ­striking workers in Glasgow's homelessness service returned to work "on the basis that an official strike ballot will be organised".

The union also held a meeting yesterday with the management of the council's social work department "to progress on a workload management scheme".

A Unison spokesman said: "Our members are content that the point has to be made about unacceptable workloads and poor staffing levels in homelessness services and indeed the wider social work department to managers, the council and the public.

"There was total unity on the decision to return to work and end the unofficial action on this basis."

Asked if the threat of the sack played a part, a union source said: "The big bad stick came out and it was going to go either of two ways; escalate the problem or end it in the short term. It seems to have had the latter effect."

A Glasgow City Council ­spokesman said: "All staff have now returned to work and we will continue our dialogue with the union on how workloads should be managed."

The action was ­triggered after a female staff member refused to take on a case involving a 16-year-old and was sent home.

It came as ­Glasgow is being forced to make £42.6 million in budget cuts, with social work and education bearing the brunt.

Unions have been involved in a long-running grievance with social work management over increased workloads.