A two-day strike by Lufthansa cabin crew was set to begin on Thursday after a German court ruled late on Wednesday against management's efforts to stop it.

The strike over pay and pensions, due to last through Friday, will result in the cancellation of 1,300 flights and affect 180,000 passengers, the German carrier said.

That amounts to about one in five of Lufthansa's planned 6,000 flights over the two-day period. It will affect both long- and short-haul flights, a spokeswoman said.

The UFO union, representing cabin crew, said it would inform the public on Thursday about a possible expansion of strikes beyond Friday.

Germany's biggest airline had filed motions with courts to prevent the strike.

The airline and the union have been at odds for months over the union's legal status. Lufthansa says a union leadership team that took office earlier this year was not elected in a way that met legal requirements.

Lufthansa said in a statement that it regretted the court decision not to block the strike. It said it would examine further legal steps, including a possible suit for damages.

"We will do everything we can to minimize the impact on our customers who are suffering from this massive strike," Lufthansa said.

Last month, the union staged an all-day strike at smaller German Lufthansa divisions, including Germanwings and Eurowings.