SIPTU shop stewards, meeting at Dublin Airport tonight, have vowed to begin industrial action if Aer Lingus suspends staff that refuse to follow company directions on Monday.
The action planned has already been decided on, but will not be made public until the result of a Sunday afternoon ballot of members is known.
Aer Lingus has said that if staff do not comply with new work practices that the company wishes to introduce on Monday morning, the staff will be suspended from duty.
SIPTU has said that this move is being implemented without agreement.
The new work practices involve staff being moved from one area of work to another during particularly busy or slack periods, specified break times, and staff remaining on duty for the full length of the shift.