BEIJING — North Korea’s national carrier has reduced the number of weekly flights connecting Pyongyang and Beijing from the start of January, a company official said Thursday, without providing a reason for the decision.

It is possible that Air Koryo cut the number of flights from three to two due to reduced tourist demand over winter and the need to save on aviation fuel, which is subject to an export ban under U.N. sanctions imposed over North Korea’s nuclear and missile programs.

The airline will continue a twice-weekly flight schedule until the end of February, the official said. Up to December 2017, Air Koryo had served the route on Tuesday, Thursday and Saturday, but has now discontinued the Thursday flights.

The carrier suspended flights connecting Pyongyang and China’s Shenyang in late December but plans to resume the service in mid-January.

Air China also serves the Pyongyang-Beijing route but the Chinese airline suspended flights in late November due to a lack of demand. It is expected to resume the service, but no earlier than March.