The Verdi union is calling on around 20,000 Lufthansa ground staff to go on a one-day warning strike at all Lufthansa locations.
The union announced on Monday that there would be major flight cancellations and delays on Wednesday.
The warning strikes are scheduled to begin at 3:45 a.m. on Wednesday and end at 6 a.m. on Thursday.
The deputy Verdi chairperson Christine Behle, who is also the negotiator, asked the passengers for their understanding and pointed out the problematic situation of the employees, which was mainly caused by mismanagement.
Verdi informs about the upcoming warning strike in good time so that the passengers can prepare for it and possibly reorient themselves.
Verdi demands a salary increase of 9.5 percent for the ground staff at counters and in customer service, in the maintenance and freight divisions, but at least 350 euros per month for a term of one year.
In addition, the union wants to enforce a lower limit for the hourly wage of 13 euros.
According to Verdi, employees at Lufthansa Technik Logistik Services and Lufthansa Cargo are still working at rates below the future statutory minimum wage of 12 euros.
In the second round of negotiations, Lufthansa is said to have presented three variants for a package with a term of 18 months, each of which contained fixed amounts and a result-related component due on July 1, 2023.
Verdi had rejected the offer as "insufficient".
It "doesn't even come close to offsetting inflation".
Behle described the earnings-related component as a “blank check for an uncertain future for employees”.