Beer workers at the Carling plant in Burton-on-Trent, are to hold a strike ballot later this month.
The union Unite claims more than 400 staff at Molson Coors could be sacked after June 10, and reinstated on less pay.
The union says nearly 200 workers could lose as much as £9,000 a year in wages.
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Des Coleman has the latest forecast for the West Midlands.
Des Coleman has the latest forecast for the East Midlands.
An ex-bookkeeper accused of raping and murdering a barmaid has told a jury his "over-eagerness" to satisfy her in bed caused her death.