North Korea's national carrier appears to be maintaining its policy of suspending flights between Pyongyang and Beijing, as well as to the Russian port city of Vladivostok, over the spread of the new coronavirus, sources said Wednesday. 

Air Koryo's website shows its February schedule with flights to Beijing and Vladivostok, but sources said it appears that those flights have not been in operation. 

Officials at Vladivostok International Airport and Beijing Capital International Airport also said they have not seen Air Koryo planes this month.  

Air Koryo's flights were not spotted on flight-tracking websites, like Flightradar24.

Pundits speculated that Air Koryo posted its February schedule on its website as a routine procedure, even though it doesn't plan to fly to the two cities.

Since late last month, North Korea has closed all ports of entry by land, sea and air as part of its efforts to block the COVID-19 virus from entering the country.

North Korea has not reported any case of COVID-19 virus infection, but it has called for nationwide efforts to prevent the virus from breaking out on its soil through intensified border controls and tightened quarantine processes.

Concerns are lingering that North Korea could be vulnerable as it shares a long and porous border with China and lacks key medical supplies and infrastructure to test and treat infected people. (Yonhap)