Union has flagged its unhappiness at supermarket's intention to change terms for staff who have worked for them for more than 20 years
Trade union SIPTU says it will not accept proposals from Tesco to cut the wages of long-serving staff at the company.
Tesco intends to change the employment conditions of all staff employed since before 1996.
This will hit about 1,000 workers and will mean cuts of more than €2 an hour for some staff.
Mandate trade union, which also represents Tesco workers, says staff will be at least €6,500 worse off a year after the changes.