Kim Jong-un en route to Russia for summit with Vladimir Putin

North Korean leader Kim Jong-un and Russian President Vladimir Putin were set to hold a summit in Russia soon, which could be an occasion to strengthen military cooperation between the two countries.

North Korean leader Kim Jong-un greets senior officials in Pyongyang before boarding a train to head to Russia Sunday afternoon in a photo released by the state-run Korean Central News Agency Tuesday. [YONHAP]

North Korean leader Kim Jong-un and Russian President Vladimir Putin were set to hold a summit in Russia soon, according to both countries, which could be an occasion to strengthen military cooperation between the two countries.

The North's official Korean Central News Agency (KCNA) confirmed Tuesday morning that Kim had left Pyongyang for Russia aboard his armored train Sunday afternoon, accompanied by leading officials of his ruling Workers' Party and armed forces.

He was sent off by senior officials, including Kim Tok-hun, a member of the Presidium of the political bureau of the party's Central Committee, who wished him "good health" and a "successful foreign visit," said the KCNA.

Pyongyang residents also saw leader Kim off, who was spotted in state media photos waving before boarding his private train.

The KCNA said late Monday that Kim will have talks with Putin during his visit to Russia.

The Kremlin also confirmed Monday that Kim was set to arrive in Russia at the invitation of Putin in the coming days and that a meeting between the two countries leaders would take place "shortly."

Dmitry Peskov, the Kremlin's spokesperson, said that Putin and Kim will lead their delegations in talks and could also meet "one-on-one if necessary." Putin also plans to host an official dinner for Kim.

Seoul's intelligence officials said earlier Monday that Kim had departed to Russia by train.

Putin headed for a two-day visit to Vladivostok on Monday to attend the annual Eastern Economic Forum being held at Far Eastern Federal University. The Russian president is due to speak at the forum's plenary session scheduled for Tuesday, making Vladivostok a likely venue for the meeting with Kim.

The meeting follows a New York Times report last week that Kim plans to travel to Vladivostok and that the two leaders could discuss an arms deal amid Russia's war in Ukraine.

The White House last week warned North Korea against providing any lethal weapons to Russia, saying it will "pay a price" in the international community if it does.

Kim's last overseas trip was a visit to Vladivostok, in Russia's Far East, in April 2019, which was also for a summit with Putin. North Korea recently reopened its borders following lockdown during the Covid-19 pandemic since early 2020.

Kim's luxurious, slow-moving bulletproof train is known to be equipped with the communication devices necessary to function as the leader's moving office. The train has often been a preferred mode of transportation for North Korean leaders, including the late Kim Jong-il, current leader Kim's father, who feared flying.

A green train with yellow trimmings, resembling one used by North Korean leader Kim Jong-un on his previous travels, is spotted near the North Korea border with Russia and China seen from China's Yiyanwang Three Kingdoms viewing platform in Fangchuan in northeastern China's Jilin province on Monday. [AP/YONHAP]

When Kim Jong-un met Putin in Vladivostok in April 2019, he traveled a distance of about 1,200 kilometers (745 miles) by train.

The train trip could take 20 hours or more, given rail conditions in the North.

Due to the poor condition of North Korea's rail tracks, the train is able to run at about 60 kilometers per hour (37.2 miles per hour). The rail spacing between North Korea and Russia is different, so the train's wheels could have to be changed midway.

Japanese broadcaster JNN reported Monday morning that Kim's train had arrived at Russia's Khasan Station, near the border with North Korea, and that the North Korean leader was received with a welcome ceremony, citing local authorities.

North Korean leader Kim Jong-un waves before departing on his armored train to head to Russia Sunday for a meeting with Russian President Vladimir Putin, as seen in a photo released by the state-run Korean Central News Agency Tuesday. [YONHAP]

BY SARAH KIM [kim.sarah@joongang.co.kr]