Kim Jong Un is now in Russia, ahead of an expected and closely-watched meeting with his Russian counterpart Vladimir Putin, according to Russian state news agency RIA on Tuesday.

The North Korean leader departed the capital, Pyongyang, on Sunday afternoon in a private train, accompanied by top officials, North Korean state media KCNA confirmed on Tuesday morning local time.

The train is currently traveling north through Primorsky Krai in Russia's Far East region, RIA reported.

It's not clear when or where they are expected to meet. But the Kremlin confirmed the two leaders are set to meet "within days," according to Russian state media, citing Kremlin spokesperson Dmitry Peskov.

Bilateral relations will be a priority of the talks, and a formal dinner is planned in honor of Kim's arrival, said Peskov, state media TASS reported.

Arms talks on the table: The US government said last week that such a meeting could take place as part of Russia’s efforts to find new suppliers for weapons to use in its war against Ukraine.

The two leaders met for the first time in April 2019, in the far eastern city of Vladivostok. Putin reportedly arrived in Vladivostok on Monday to attend the Eastern Economic Forum, Kremlin spokesman Dmitry Peskov said, according to state TV Russia 24.