North Korean leader Kim Jong-un's de-facto chief of staff was seen in Vladivostok amid speculations regarding Kim's visit to Russia next week. 

Japan's Fuji News Network reported that Kim Chang-son, the chief secretary of the Secretariat of the North's State Affairs Commission, was seen inspecting the surroundings of the Vladivostok train station on Wednesday afternoon.

The media outlet also published a photo of the chief secretary next to the station.

Kim Chang-son is known to be in charge of logistical preparations for his leader's overseas trips and often travels to the locations which Kim Jong-un is set to visit.

The official's visit comes amid reports that Russia is seeking a summit with Kim Jong-un during Russian President Vladimir Putin's trip to the Far East next week. 

There is speculation that the summit could take place before the One Belt, One Road Forum scheduled to take place in Beijing next Friday and Saturday. Putin is expected to attend the forum.