Deutsche Lufthansa AG, Europe's second-biggest airline, is facing disruptions after the pilots' union called on workers to stage strikes over pay.

The walkouts started at midnight and will last for 24 hours, affecting flights from all major German airports including the main Frankfurt hub, the Vereinigung Cockpit pilots' union said in an e-mailed statement yesterday. Flights at Lufthansa's regional Cityline and Eurowings carriers will be affected.

Lufthansa faces the second round of strikes after walkouts ranging from check-in staff to baggage handlers and catering workers on July 1 forced the airline to cancel at least 44 flights. Demands for higher wages come after the price of crude oil touched a record $145.85 a barrel on July 3, putting pressure on carriers to raise prices to shore up earnings.

"It's too early to give details on the possible extent of disruptions," said Lufthansa spokeswoman Renate Hocke in a telephone interview. "We try to keep effects as limited as possible" and flight cancellations can't be ruled out.

The airline industry may suffer losses of as much as $6.1 billion this year based on oil at $135 a barrel, the International Air Transport Association, representing 230 carriers, said last month. European operators including Luton, England-based Silverjet Plc have already stopped flying.

In Germany, the Ver.di labor union began strikes on June 19 in a dispute over wages for Cologne-based Lufthansa's 48,000 German flight attendants and ground workers. The union wants a pay increase of 9.8 percent, while the airline is offering 5.5 percent in two steps.

Lufthansa fell 21 cents, or 1.5 percent, to 13.48 euros in Frankfurt on July 4. The stock has shed 26 percent this year, valuing the company at 6.17 billion euros ($9.69 billion).

The Cockpit union, with some 8,200 members, couldn't be reached for comment on pending strikes.