Updated June 18, 2024 at 14:30 PM ET

SEOUL, South Korea — President Vladimir Putin of Russia has arrived in North Korea for a summit with leader Kim Jong Un.

Their meeting, the second in nine months, is a sign of the two countries' deepening political and military partnership built over Russia's war in Ukraine.

Putin arrived early Wednesday morning, with the two leaders expected to meet later in the day. It is Putin's first trip to North Korea since 2000 and the first visit in North Korea by a head of state since the country shut its borders in 2020.

Putin and Kim last met in Russia's Far East in September, where Putin showed Kim around Vostochny spaceport and vowed to help North Korea's satellite development.

Pyongyang and Moscow cooperate on Ukraine

North Korea has consistently supported Russia from the early days of the war in Ukraine, voting against the United Nations resolution condemning Russia's invasion and joining Russia in recognizing Luhansk and Donetsk as independent states.

The United States and South Korea suspect North Korea has also been providing Russia with large quantities of artillery shells and other munitions for use against Ukraine, a claim that North Korea has denied.

South Korean Defense Minister Shin Won-sik said in a recent interview that North Korea could have shipped as many as 5 million shells and dozens of ballistic missiles to Russia.

Shin has said that Russia, in return, has been easing North Korea's economic hardships by sending containers likely filled with food and other aid.

Russia also has paid Pyongyang back with a political favor, voting to disband a North Korea sanctions monitoring panel at the United Nations Security Council in March.

In the past year, the two increasingly isolated countries have engaged in a flurry of bilateral diplomatic and cultural exchanges, including visits by North Korea's foreign minister and Russia's defense minister. In the same period, Kim Jong Un made frequent appearances at weapons factories and test sites.

In a letter published in North Korea's official Rodong Sinmun newspaper ahead of his visit, Putin praised North Korea for its support of Russia's war and characterized the two countries as fighting a similar struggle against the U.S. and its allies.

He pledged the two countries will "develop alternative trade and mutual settlement mechanisms not controlled by the West" and "build an equal and indivisible security architecture in Eurasia" while increasing people-to-people exchanges.

Putin's foreign policy aide Yuri Ushakov said the leaders may sign a comprehensive strategic partnership treaty that will replace earlier bilateral treaties.

Why the bilateral relations aren't expected to expand

But North Korea watchers in South Korea and the U.S. doubt the relationship will expand much further from the current transactions.

"The upcoming visit will likely be a kind of political lip service," says Cho Han-bum, a researcher at the Korea Institute for National Unification, a government think tank in Seoul. It can help Putin keep Kim Jong Un's support during the prolonged war, while elevating Kim's stature at home and abroad, he says.

"Once the war in Ukraine ends, North Korea will no longer be important to Russia," says Cho.

The volume of trade between Russia and North Korea is minimal compared with Russia's trade with South Korea or North Korea's trade with China.

Relations with South Korea are part of the reason Russia would be careful about making major offerings to the North, such as advanced military technology transfers or a mutual defense treaty, according to an analysis by the Institute for National Security Strategy, a think tank affiliated with South Korea's top intelligence agency.

Even if the two countries agree to a higher level of military cooperation, they would be reluctant to formalize or announce it, says Jenny Town, the director of the Korea Program at the Stimson Center, a foreign affairs think tank in Washington, D.C.

Not only are many of North Korea's military activities under sanctions, but also the country stresses self-reliance and shuns appearing dependent on other countries.

How China figures into North Korea-Russia ties

Still, Russia and North Korea may see each other's value as a strategic partner in their opposition to the U.S.-led world order, especially given China's elusiveness, says Town.

"Russia is willing to be bold, is trying to upend the system," she says, "whereas China is still trying to be part of that system and trying to have some governance role in that system."

China held high-level talks with South Korea on Tuesday, just hours before Putin's expected arrival in Pyongyang. And the leaders of China, Japan and South Korea held a trilateral summit last month for the first time in over four years.

"China still talks about denuclearization whereas the Russians seem to have generally accepted North Korea as a country that's nuclear armed," adds Town.

In an interview with Russia’s state media in March, Putin said North Korea "has its own nuclear umbrella."

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