Kim Jong Un reportedly hops on his bulletproof, drab green train for meeting with Putin

A luxury armored train believed to be carrying Kim Jong Un appeared to depart Pyongyang Monday for Vladivostok, Russia, where the reclusive North Korean leader may rendezvous with President Vladimir Putin.

South Korean state media reported that the train Kim uses, bulletproof but notoriously slow possibly because of its weight, left North Korea. The Kremlin confirmed in a statement that Kim would visit Russia "in the coming days."

The White House has said it was expecting a meeting between the two leaders this month as Moscow looks to its ally from the Soviet era to help it rearm for its war in Ukraine. The meeting could take place as early as Tuesday. It would be Kim's first overseas trip in more than four years.

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The White House said last week that arms negotiations between North Korea and Russia were "advancing." It also warned that Kim's regime would "pay a price" if it strikes an arms deal with Putin's government.

The encounter between Kim and Putin could take place on the sidelines of the annual Eastern Economic Forum. It runs in the far eastern Russian port city through Wednesday, according to its website.

South Korea's Yonhap news agency has reported that Kim's train has up to 20 bulletproof carriages and has a top speed of about 37 mph. It is painted drab green and is rarely photographed. The train was used by Kim's father and grandfather, both of whom were leaders of North Korea.

The isolated Asian country could help resupply Moscow with artillery shells and rockets. The Carnegie Endowment for International Peace, a Washington think tank, describes North Korea's munitions industry as "highly developed." In return, North Korea could seek access to some of Russia's high-tech weapons systems.

North Korea continues to test and develop long-range ballistic missiles and nuclear weapons. The U.S. and North Korea have held nuclear nonproliferation talks on and off stretching back to the 1980s.

This article originally appeared on USA TODAY: Kim Jong Un, Vladimir Putin meeting expected in 'coming days'