In a rare show of strength, North Korean leader Kim Jong-un arrived in Russia on Tuesday to hold a summit with Russian President Vladimir Putin, with concerns growing over a possible arms deal between Pyongyang and Moscow, an official at South Korea's Defence Ministry said.

The North's official Korean Central News Agency (KCNA) confirmed early Tuesday that Kim had left Pyongyang for Russia aboard his bulletproof train on Sunday afternoon, accompanied by leading officials of the regime's ruling party and the armed forces, reports Yonhap News Agency.

The KCNA said Kim "left here by his train on Sunday afternoon to visit the Russian Federation", without saying whether the train had crossed its border.

Hours after the KCNA report, Jeon Ha-kyou, a spokesperson at the South Korean Defence Ministry, gave an assessment that Kim's train had crossed into Russia early Tuesday, adding that Seoul was closely monitoring for possible talks between the two countries over arms trade.

Kim Jong-Un Arrives In Russia For Rare Summit With Putin
Kim Jong-Un Arrives In Russia For Rare Summit With PutinIANS

"Considering that a large number of military personnel is accompanying him, (we) are closely monitoring whether negotiations over arms trade between North Korea and Russia, and technology transfers will take place," Jeon told reporters.

Russian media outlet "Vesti Primorye" also reported that Kim's train arrived at the border city of Khasan on Tuesday and is on its way to the Far Eastern city of Ussuriysk, citing a railway source.

The train passed through Khasan station early Tuesday and is already in the Primorsky Krai region, according to the Russian media report.

Photos released by the North's state media showed Kim being accompanied by Pyongyang's Foreign Minister Choe Son-hui, as well as top military officials Ri Pyong-chol and Pak Jong-chon.

It still remains unknown exactly when and where Kim and Putin would hold a meeting, and the North Korean leader's whereabouts also remain unclear.

The Kremlin said negotiations between North Korean and Russian delegations are planned during Kim's visit, with discussions over the possibility of a one-on-one meeting between the leaders.

The trip would mark the first such visit to Russia by Kim in more than four years and his first trip abroad since the outbreak of the Covid-19 pandemic.

French Wine, Live Lobsters, Perfomers - A Peek Inside Kim Jong-Un's Luxury Bulletproof Train
French Wine, Live Lobsters, Perfomers - A Peek Inside Kim Jong-Un's Luxury Bulletproof TrainIANS

Pyongyang has recently been seeking to bolster military ties with Moscow in the wake of growing security cooperation among South Korea, the US and Japan.

Earlier this month, The New York Times had reported that Kim was planning to travel to Vladivostok, possibly by armoured train this month, for talks with Putin about the possibility of supplying Russia with ammunition and weaponry for its war in Ukraine and other military cooperation.

As both North Korea and Russia confirmed Kim's visit to Russia, the US called on Pyongyang not to provide any weapons to Russia.

Adrienne Watson, spokesperson for the White House National Security Council, underscored that North Korea and Russia will likely continue discussing a potential arms deal during the Kim-Putin meeting.

"As we have warned publicly, arms discussions between Russia and the DPRK are expected to continue during Kim Jong-un's trip to Russia," Watson told Yonhap News Agency when asked to comment on Kim's visit to Russia.

"We urge the DPRK to abide by the public commitments that Pyongyang has made to not provide or sell arms to Russia," she added.

DPRK stands for the Democratic People's Republic of Korea, North Korea's official name.

(With inputs from IANS)