Korean Air has become the latest carrier to suspend its flights to Moscow since the Ukraine conflict began, while Japanese airlines are extending their cancelation of most European flights.

Korean Air has canceled its services between Seoul Incheon and Moscow Sheremetyevo until March 18 citing difficulties in obtaining jet fuel in Russia. “We were informed by a Russia-based refueling service provider this afternoon that we can no longer refuel our planes at the airport in Moscow,” a Korean Air spokesman said March 4.

The airline’s other flights destined for Europe will continue to overfly Russian airspace. Korean Air said it is “monitoring and assessing the situation around the clock, and [has] in place contingency plans for flight operations.”

Japan Airlines and All Nippon Airways had previously canceled almost all of their European flights scheduled for March 3-4 due to their decisions to avoid flying over Russian airspace.

JAL has now extended the suspensions through March 7. The only exception is a flight from Tokyo to London, which has been rerouted to fly northeast over Alaska instead of west over Russia.

ANA has canceled its flights to London and Paris, and some of its Frankfurt flights, through March 10. However, it will continue to operate its flights to Brussels and some Frankfurt services during this period. The operating flights will be rerouted over central Asia.