The future of Boeing’s 737 Max model is still unclear — and a Chinese aviation giant is getting impatient.

China Eastern, one of China’s largest airlines, has formally requested compensation from Boeing for losses that have been caused by flights affected by the model's safety concerns, the company confirmed to Caixin on Monday. China Eastern is the first Chinese company to confirm such a demand.

In March, the Civil Aviation Administration of China (CAAC) grounded all Boeing 737 Max jets in China, citing safety fears after the second deadly crash by that model of aircraft in five months. CAAC did not give a timeline for the resumption of flights.

China Eastern did not say how much it is asking for in compensation. The company also told Caixin it had not discussed the compensation plan with other aviation companies, though an earlier Bloomberg report said that some were considering raising compensation requests together.

Boeing declined to comment on the issue.

Up until the March announcement, China Eastern operated 14 Boeing 737 Max planes.

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