Several state-owned Chinese airlines have begun canceling international flights due to rising global fuel prices, according to reports confirmed by travelers to CNN. The cancellations include routes to destinations such as Southeast Asia and Australia. Passengers have reported receiving messages from airlines including Sichuan Airlines and China Eastern Airlines, informing them that their late-April flights have been canceled.

The sudden cancellations have left some Chinese tourists stranded abroad. One traveler in Melbourne said her return flight to China was canceled, disrupting her work schedule. Another student from Hebei province expressed disappointment after her planned trip to Thailand was canceled. The disruptions come just before the five-day Labor Day holiday in May, one of China’s busiest travel periods when many citizens plan overseas trips.

Although no Chinese airline has made a public announcement, both Sichuan Airlines and China Eastern Airlines confirmed to CNN that the cancellations were part of policy adjustments.