Some 300 flights were either scrapped or rescheduled, the airport said, affecting around 35,000 passengers.

The day-long “warning strike” was called by the powerful Verdi union to ramp up pressure ahead of the next round of negotiations with bosses.

The union said it expected some 1,500 airport employees to take part in the walkout.

Verdi is pushing for a monthly salary increase of €500 over a 12-month period for ground crew. For security personnel, it wants higher bonus payments for weekend and holiday hours.

“Everyone knows about the exorbitantly higher prices, be it for food or at petrol stations,” Verdi representative Holger Roessler told German media. German inflation slowed to 8.6 percent in December after peaking at 10.4 percent in October, mainly thanks to government relief measures to cool energy costs.

Late last year, Germany’s biggest trade union IG Metall won an agreement for an 8.5-percent pay hike covering almost four million workers in industrial sectors after staging a series of warning strikes.

Under EU law, airline passengers are normally entitled to up to €600 in compensation if their flight is cancelled, overbooked, or delayed for more than three hours. However, this applies only if the airline is responsible for the flight’s delay or cancellation—not if someone else is, like the airport authority, as in this case.

Easyjet, one of the largest operators out of BER, says the airline will contact affected customers directly.

“While this is out of our control, we’re doing everything we can to minimise the inconvenience to our customers,” a company spokeswoman told regional newspaper Berliner Morgenpost.

“Affected customers have the option to rebook their flight or receive a refund. Hotel accommodation and meals are provided where required.”

Almost 20 million passengers passed through BER in 2022.

READ ALSO: What are your rights in Germany if your flight is delayed or cancelled?