German airline Lufthansa said Wednesday it will cancel nearly 500 European flights on Thursday owing to planned warning strikes by ground staff and other divisions within the group.

"Due to announced strikes of Lufthansa staff at the airports Frankfurt, Munich, Duesseldorf, Berlin, Hamburg and Cologne as well as several other locations on March 21, between 5:00 a.m. and midday (0400-1100 GMT), Lufthansa will cancel most of its domestic and short-haul flights. Long-haul flights are expected to operate on time," the carrier said on its website.

Earlier, the giant services sector union Verdi had called for walkouts to increase the pressure on management ahead of a second round of pay talks for around 33,000 ground staff and staff of the subsidiaries Lufthansa-Systems, Lufthansa Service Group (LSG), Lufthansa Technik and Lufthansa Cargo on Friday.

Verdi is demanding a pay increase of 5.2 percent plus job guarantees.

Lufthansa management had offered zero-wage increases for two years and longer working hours, an "affront to all Lufthansa employees," the union said.

The ADV airports federation rejected the new wave of walkouts however.

"The warning strike is bad news for German airports and thousands of passengers," said ADV chief Ralph Beisel.

"Once again, a conflict between the wage-negotiating partners is being carried on the backs of passengers," he remarked.