The main cabin crew union at Lufthansa dismissed an effort by management to avert a potential week-long strike by calling the airline's latest proposals a "PR stunt".
Flight attendants' union UFO had said on Monday it would call for a strike on November 6-13 if Lufthansa did not put forward a serious offer by Thursday evening in a long-running row over pension costs and early retirement benefits.
The airline earlier on Wednesday said the demands of the cabin crew union would increase costs by 25 percent, but that it would send the union four new variants of its previous offer as a basis for new talks.
Nicoley Baublies, head of the UFO union, described that as "old wine in new bottles" and confirmed plans to strike should a new offer not be forthcoming.
Lufthansa, which is negotiating with various staff groups to cut costs and reduce its pension burden by moving to defined-contribution from defined-benefit schemes, also said the threat of strike action had resulted in more customers cancelling flights this week than usual.
Along with the cabin crew row, the airline is still in talks with pilots' union Vereinigung Cockpit over pay and retirement benefits. Talks also commence on Thursday with union Verdi concerning retirement benefits for around 33,000 ground, cargo and other cabin crew staff.
The cabin crew union had previously threatened strikes over the summer but backed down after Lufthansa offered a compromise. The pilots' union has staged strikes this year, most recently in September.