By Peter Maushagen
FRANKFURT (Reuters) - A German cabin crew union gave the country's largest airline Lufthansa (DE:LHAG) a June 30 ultimatum to make concessions in a row over pay and pensions, threatening intermittent strikes until mid-September that could compound a costly labor dispute with its pilots.
Lufthansa is in protracted talks with various staff groups as it seeks to bring down costs and revamp pension schemes to better compete with low-cost airlines and expanding Middle Eastern rivals.
The UFO flight attendants' union said at a press conference on Monday that if an accord was not reached with Lufthansa by June 30, its members would strike the following day with a schedule of more strike days to be announced thereafter that could last to Sept. 16.
UFO, which represents 19,000 cabin crew at Lufthansa, said on Saturday it would not resume talks with the company after mediation failed.
The airline has said it was prepared to resume talks with the union.
Lufthansa has already been hit by over a dozen walk-outs over the last year by its pilots, who are also in talks over pension benefits and pay and are now also in a mediation process, ruling out strikes until the end of July.
The carrier's stock pared gains to trade up 1.2 percent at 0854 GMT, making it the weakest performing stock in Germany's blue chip DAX (GDAXI) index, which was up 3.3 percent.
