North Korean leader Kim Jong-un’s private jet is known to have flown to and from Vladivostok on Monday, stoking speculation that he is preparing to visit Russia.

According to Flightradar24, a flight tracking Web site, the Chammae-1 flew over North Korea's eastern coast and arrived in the Russian city near the border between the two countries in the morning, and then returned to the North via the same route three hours later. 

Vladivostok is the venue for the Eastern Economic Forum Russian President Vladimir Putin is scheduled to host in September. 

It is believed that a working-level delegation from Pyongyang flew to the Russian city on Kim’s private jet to help arrange his possible attendance at the annual forum. 

In May, Russian Foreign Minister Sergei Lavrov visited Pyongyang to deliver an invitation from Putin to Kim.

[Photo : YONHAP News]