German cabin crew union UFO rejected latest offer of Lufthansa on Monday. The union would go ahead with further strike action as planned for Tuesday which is set to affect more lucrative long-haul flights. Cancellations could continue until Friday.
Lufthansa tried to win over striking cabin crew staff by increasing a one-off payment offer by 1,000 euros to 3,000 euros and promising a 1.7 percent pay rise next year and in 2017.
Lufthansa said on Monday it was losing at least 10 million euros ($10.8 million) a day from the longest strike in its 60-year history as cabin crew confirmed a fourth day of strikes for Tuesday.
Lufthansa is trying to negotiate with staff groups to bring down pension costs as part of a savings drive to allow it to compete better with low-cost rivals and wealthy Gulf carriers.
Strikes by pilots have already cost Lufthansa 130 million euros so far this year.
Lufthansa said on Monday it would re-assess low-profit routes to Asia, Africa and South America from 2016 onwards to address cost issues.
Passengers should check their flight status before leaving to the airport.