1 of 7 | North Korea's Kim Jong Un arrives in Russia by train after crossing the border at Khasan, south of Vladivostok, on Tuesday. Photo by Russian Ministry of Natural Resources and Ecology | License Photo
SEOUL, Sept. 12 (UPI) -- North Korean leader Kim Jong Un has arrived by train in Russia for a summit with President Vladimir Putin, South Korea's military said Tuesday, amid widespread speculation that Pyongyang is planning to supply munitions to Moscow for its war on Ukraine.
Kim crossed the border into Russia in the early hours of Tuesday morning, Seoul's Defense Ministry told reporters in a text message.
Earlier on Tuesday, North Korean media reported that Kim had left Pyongyang by armored train for Russia on Sunday afternoon.
Images released by state-run Korean Central News Agency showed the North Korean leader smiling and waving from his armored train, which he has used for previous visits to Russia, China and Vietnam. Kim appeared to be accompanied by Foreign Minister Choe Son Hui and military officials Ri Pyong Chol and Pak Jong Chon.
Kim's train is weighed down by heavy bulletproof carriages and moves at speeds of less than 40 mph, according to South Korean media reports. It also has to stop at the North Korea/Russia border and change wheels to fit Russian railroad tracks.
On Monday, the Kremlin also confirmed that Kim was coming to Russia, saying he would arrive for an official visit at the invitation of Putin "in the coming days."
The two leaders are expected to meet in the port city of Vladivostok, where Putin is attending the Eastern Economic Forum on the campus of Far Eastern Federal University.
The summit will mark Kim's first international trip since 2019, when he also visited Putin in Vladivostok after a summit with former U.S. President Donald Trump failed to reach an agreement on nuclear disarmament.
The White House said last week it had information that arms negotiations between Russia and North Korea were "actively advancing" and warned that the North would "pay a price" if a deal goes through.
According to a New York Times report, Putin is seeking artillery shells and anti-tank missiles, while Kim wants advanced technology for satellites and nuclear submarines -- as well as food aid for his impoverished country.
U.S. State Department spokesman Matt Miller said Monday the potential arms deal was a sign that Putin's full-scale invasion of Ukraine, launched in February 2022, is failing in the wake of global sanctions against its war effort.
"There's no better evidence of that than now, a year and a half later, not only has [Putin] failed to achieve his goals on the battlefield, but you see him traveling across his own country hat in hand to beg Kim Jong [U]n for military assistance," Miller said at a press briefing.
Moscow and Pyongyang have drawn closer amid a growing geopolitical divide sparked by the invasion of Ukraine, with Putin and Kim exchanging letters earlier this year vowing to deepen bilateral cooperation.
In July, Russian Defense Minister Sergei Shoigu visited Pyongyang, where he toured a weapons expo and viewed a military parade, sparking concern about a pending arms sale.
Russia, along with China, has repeatedly blocked U.S.-led efforts at the United Nations Security Council to take action against North Korea over a flurry of weapons tests, including its launch of a Hwasong-18 intercontinental ballistic missile in July.