Lufthansa cancelled almost 1,000 regional flights at subsidiaries Eurowings and CityLine as pilots walked out in a pay dispute.

On Tuesday alone, 465 flights were scrapped, a Lufthansa spokesman said. The airline expected another 525 cancellations on Wednesday.

The Vereinigung Cockpit (VC) pilots' union called on its members to walk out from 1000 GMT on Tuesday until 2200 GMT on Wednesday.

The strike affected passengers at airports across Germany, including Lufthansa's main hubs at Frankfurt and Munich. CityLine and Eurowings together operate almost 700 of some 1,800 daily Lufthansa group flights.

The dispute between the pilots and Lufthansa has been going on for months. A 24 hour strike at the start of July led to the cancellation of hundreds of Eurowings and CityLine services.

Lufthansa says it has offered CityLine pilots a 5.5 percent raise plus one-off payments over 18 months. It has offered Eurowings staff a 6.5 percent pay rise over 24 months plus one-off payments.

VC says it has not obtained a suitable offer so far.

In a separate dispute over pay for ground staff and cabin crew, Germany's Verdi trade union is holding a ballot at Lufthansa on possible strikes later this year. The conflict has raised concerns of chaos for thousands of passengers during the busy summer travel period.