Lufthansa has cancelled about two-thirds of its flights after cabin crews walked out at airports around the country in an escalating battle with Germany's largest airline.
However, signs are emerging that the two sides may be prepared to return to the negotiating table.
UFO union chairman Nicoley Baublies told the Associated Press at Frankfort airport that he had talked on the phone with Lufthansa during the night, and that the two sides had agreed to call in a mediator to help them settle their dispute.
The flight attendants, represented by the UFO union, walked out at midnight on Thursday in a 24-hour strike.
The dispute comes as Lufthansa struggles to fend off challenges from budget carriers and government-owned airlines in the Persian Gulf.