UFO, which represents more than 12,000 flight attendants and pursers in Germany, said on Wednesday 97.5 percent of workers who participated in a ballot have already voted in favour of industrial action.

The strike threat comes just as Lufthansa plans to cut 3,500 jobs - about 3 percent of its global workforce of 117,000 - to help improve earnings by 1.5 billion euros by 2014 to offset soaring fuel prices and fierce competition from low-cost carriers and Middle East airlines.

UFO said Lufthansa is due to present a new wage offer on August 16, after more than a year of negotiations, and said it would decide after that whether to go ahead with a strike.

"It is now up to the employer and its willingness to reach an agreement to show whether it has understood the signal of its employees," UFO chief Nicoley Baublies said in a statement.

A spokesman for Lufthansa said talks were still ongoing with UFO. "They have neither failed nor been called off," he said.

UFO is pushing for higher wages after three years without a pay increase as well as an agreement by Lufthansa not to staff flights with temporary workers. The union had hit back at plans by Lufthansa to hire temporary staff as flight attendants on its routes from Berlin, but a German court backed the airline earlier this year.

In an effort to cut costs, Lufthansa has frozen investments, shifted contracts of pilots and flight attendants at carrier Austrian Airlines to a lower-cost subsidiary and is boosting cooperation between its main Lufthansa brand and low-cost carrier Germanwings.

But Lufthansa (LHAG.DE) just posted quarterly operating profit that was much better than expected and said it saw no downturn in demand for air travel in Europe, which could weaken its bargaining position. (Reporting by Peter Maushagen; Writing by Maria Sheahan; Editing by Mike Nesbit)

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