North Korea and Russia have confirmed North Korean leader Kim Jong Un will visit Russia for talks with Russian President Vladimir Putin.

The Kremlin said on Monday Kim’s visit was at Putin’s invitation and would take place “in the coming days”. The official visit was also reported by North Korea’s KCNA state news agency, which said he would meet Putin soon.

Putin arrived in the Russian far eastern city of Vladivostok on Monday to attend the Eastern Economic Forum. The city was also the site of Putin’s first meeting with Kim in 2019.

Earlier on Monday, South Korean media, quoting unnamed government sources, reported that Kim appeared to have left on a special train bound for Russia for a summit with Putin that could take place as early as Tuesday.

Kim does not travel abroad often and, when he does, it is often shrouded in secrecy and security. He travels by train with signature olive green carriages said to be armoured and equipped with communications systems, along with a personal suite for Kim to work and confer with aides.

‘Without fear of consequences’

The meeting between Kim and Putin will likely focus on military cooperation, and possibly a deal to supply arms, US and South Korean officials and analysts say.

The United States has said it would be a “huge mistake” for North Korea to supply Russia with weapons to use in Ukraine and warned Pyongyang would “pay a price”.

The deepening relationship between Kim and Putin signals a further global split over the war, said Ramon Pacheco Pardo, the Korea Chair at the Brussels School of Governance.

“North Korea’s support will allow Putin to wage his war for longer, which is bad news for Europe,” he said. “It is further proof that much of the world doesn’t support Ukraine in the way the US and Europe do, and some countries such as North Korea will openly support Russia without fear of any real consequences.”

North Korea has possibly tens of millions of artillery shells and rockets based on Soviet designs that could potentially give a huge boost to the Russian army, analysts say.

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In exchange, Kim could seek badly needed energy and food aid and advanced weapons technologies, including those related to intercontinental ballistic missiles, nuclear-capable ballistic missile submarines and military reconnaissance satellites, analysts say.

There are concerns that potential Russian technology transfers would increase the threat posed by Kim’s growing arsenal of nuclear weapons and missiles that are designed to target the United States, South Korea, and Japan.

Associated Press journalists near the North Korea-Russia frontier saw a green train with yellow trim – similar to the train used by Kim during previous foreign trips – at a station on the North Korean side of a border river.

It was unclear whether Kim was on the train, which was seen moving back and forth between the station and the approach to the bridge that connects the countries. It had not crossed the bridge as of 7pm (10:00 GMT).