Unite union members at the Manchester site of the Fujitsu IT firm are to ballot for strikes against a number of attacks on the union, including the threat to dismiss Crewe rep Alan Jenney.
Ballot papers are to be sent out on Friday.
Members at the Crewe site struck in defence of Alan on 30 June, and are continuing to take action short of a strike.
The firm planned to dismiss Alan on Monday of this week after turning down a second worker who had volunteered to take his place.
The union believes that Alan is being targeted because he is a rep.
Fujitsu intends to dismiss Alan even though he has outstanding appeals and grievances.
Fellow workers showed their support for Alan by joining protests and meetings at Fujitsu sites around the country on Thursday of last week.
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