In a statement on its webpage, Ver.di slammed the Federal Association of Aviation Security Companies (BDLS) for not submitting any negotiable proposals on pay rise, despite earlier warning strikes by the security staff.
The union said it has decided to expand the planned warning strike at Frankfurt Airport on Tuesday to seven other airports, including Munich, Hamburg, Bremen, Hanover, Leipzig, Dresden and Erfurt.
The security personnel at Frankfurt Airport will stop performing their duties on Tuesday between 2 a.m. (0100 GMT) and 8 p.m. (1900 GMT).
In other airports, local branches of the union will decide at what time the strike will take place.
Ver.di, a major trade union representing around 23,000 security staff, is demanding a minimum wage of 20 euros (nearly $23) per hour for its members.
The next round of negotiations between the union and the employers' association BDLS is slated for Jan. 23.
More about: Germany