Unions have held protests outside around 200 stores of Switzerland’s largest retailer, Migros, calling for higher salaries and better working conditions.
The company, which employs 80,000 people, dismissed Thursday’s action as a "publicity stunt" aimed at attracting new union members.
Union officials circulated flyers to staff accusing the company of violating employees’ rights.
Migros denounced the claims as unfounded and announced it would hold a press conference on Friday to defend its position.
"These demonstrations are simply a publicity stunt by the unions to attract more members. Only three per cent of staff at Migros belong to a union,” Urs-Peter Naef, spokesman for Migros, told swissinfo.
Unions claim that Migros pays salaries that are below the industry average, with skilled workers and senior staff worst affected. The company denies the allegations.
Migros rejects criticism
On Wednesday Migros issued a statement stating that it had increased salaries over the past four years by ten per cent, boosting wages by SFr400 million ($324 million).
Union leaders were unimpressed and stood outside Migros stores handing out tissues as a sign that the situation was “to cry for”.
"Today's action is designed to let staff know who we are and show that we will support them in the future," Fabienne Millioud, a union official, told swissinfo.
Unions clashed with the retailer last August when Migros said it would stop dealing with one of the trade unions representing employees by the end of this year.
It also cancelled the union's collective labour agreement.
"We object to the fact that Migros excludes some unions from its collective contracts even though they haven't done anything wrong," said Millioud.
Migros says it doesn’t understand why it is being targeted by the unions.
“The collective labour agreement for 2003 to 2006 is still valid and everyone's contracts remain unchanged,” said Naef.
Unions also claim that Migros - dubbed the “orange giant” - is keeping its employees from meeting union representatives.
“We are not allowed to enter the Migros anymore,” said Andreas Rieger, a union official.
Union leaders filed a lawsuit against the Migros cooperative in Basel last November claiming violation of union rights.
Despite problems with its workforce, Migros announced positive financial results earlier this month.
The company reported a one per cent increase in overall sales to SFr20 billion ($16.4 billion) for 2003.
Migros employs 80,000 people.
About 3% of staff belong to a trade union.
The Migros Group posted sales of SFr20 billion in 2003.
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