Head of the UFO cabin crew union Nicoley Baublies told a press conference in Frankfurt that the call to strike would be issued without warning in the coming weeks. Head negotiator Dirk Vogelsang stressed that the strike would not begin on Tuesday.
A Lufthansa spokeswoman told The Local that the airline could not undertake specific measures to minimize the impact to passengers until it knew when the strike would happen.
The airline is considering taking legal action to halt the strike, Lufthansa personnel manager Peter Gerber told a Frankfurt press conference on Tuesday afternoon.
UFO and Lufthansa are currently at loggerheads over a collective wage agreement that governs fees and salary levels. Lengthy negotiations overnight from Monday to Tuesday ended in deadlock.
Lufthansa said UFO's demands were too high. The union is calling for a five percent raise and an end to the airline's practice of employing lower-paid temporary workers.
UFO's negotiator Dirk Vogelsang insisted that Lufthansa had offered too little and wouldn't budge on structural issues. UFO fears that up to 2,000 flight attendants could be transferred to a Lufthansa subsidiary and paid less.
"If it says Lufthansa on the outside, it has to be Lufthansa on the inside," said Vogelsang.
Except for minor warning strikes in 2009, Lufthansa flight attendants have never gone on strike.
UFO says it has mobilized more than half of Lufthansa flight attendants; members are to be called to action by email and text message.
Lufthansa is scheduled to hold a press conference on Tuesday afternoon to offer more details on its negotiations with UFO.