German airline Deutsche Lufthansa AG reported a first-quarter loss of (EURO)397 million ($521.3 million) on Wednesday, blaming high prices for fuel and other expenses.

In the same period last year the airline reported a net loss attributable to shareholders of (EURO)507 million.

Lufthansa's operating loss widened to (EURO)381 million, from a year-ago loss of (EURO)169 million, despite a 5.6 percent rise in revenue to (EURO)6.6 billion.

"The additional revenue could however not offset the cost increases, in particular for fuel," the airline said in a statement released ahead of its full earnings report Thursday.

The International Air Transport Association said Wednesday that with oil prices remaining stubbornly above $100 a barrel over the past year, the airline industry is suffering.

"Jet fuel prices have risen 8 percent since January. Considering that fuel now accounts for 34 percent of average operating costs, it's an increase that hurts," said IATA's chief executive Tony Tyler.