Labour-run Kirklees council in West Yorkshire issued another 1,500 HR 1 redundancy notices to its workers last week.
This comes of top of the 1,100 already issued.
The Kirklees Unison union branch has called for the reinstatement of the strike ballot that was put on hold after the council offered talks.
The Unite and GMB unions at the council have now also announced that they will be balloting alongside Unison.
Notification of Unison’s ballot was expected to be given to the council this week.
The branch is looking to take a five-day strike early in the new year.