Russian President Vladimir Putin is set to arrive in North Korea later on Tuesday, marking his first visit in 24 years, highlighting the growing connection between the two nuclear-armed nations.

North Korean leader Kim Jong Un extended the invitation to Putin during Kim's visit to Russia’s eastern region in September, the first interaction between the leaders since 2019.

"At the invitation of the Chairman of State Affairs of the DPRK, Kim Jong Un, Vladimir Putin will pay a friendly state visit to the Democratic People’s Republic of Korea on June 18-19," the Kremlin announced on Monday, using North Korea’s formal name.

North Korea’s state news agency, KCNA, confirmed the visit but did not provide additional details.

Putin last visited Pyongyang in July 2000, shortly after his initial election as president. He met with the then-leader, Kim Jong Il, Kim Jong Un’s father.

In a letter published in Tuesday's edition of Rodong Sinmun, the newspaper of North Korea’s ruling Workers’ Party, Putin emphasized that the two nations have developed strong relations and cooperation over the past seven decades based on equality, mutual respect, and trust.

"We will develop alternative trade mechanisms and mutual settlements that are not controlled by the West, and collectively oppose illegitimate unilateral restrictions," Putin wrote. "Simultaneously, we will construct an architecture of equal and indivisible security in Eurasia."

He expressed gratitude to North Korea for its support of Russia’s war in Ukraine and assured support for Pyongyang in defending its interests against "US pressure, blackmail, and military threats."

'Axis of transactionalism'

Concerns are rising that Pyongyang is supplying Moscow with essential munitions for the war in Ukraine in return for economic assistance and technology transfers to support Kim’s military modernization program initiated in recent years.

Last week, South Korea and the United States discussed the upcoming visit and expressed concerns over the potential regional security implications of the closer ties between the two nations.

"For Kim Jong Un, this visit is a triumph," said Leif-Eric Easley, a professor of international studies at Ewha Womans University in Seoul, in emailed remarks. "The summit not only elevates North Korea’s status amongst countries opposing the U.S.-led international order but also bolsters Kim’s domestic legitimacy."

"While Russia cannot replace China economically, increased cooperation with Moscow shows that Pyongyang has options. For now, Putin’s war in Ukraine establishes an ‘axis of transactionalism’ among sanctions violators looking to trade older weapons for current military technology."

Two months following his Russia visit, North Korea announced that it had successfully launched a spy satellite into orbit after two previous failures.

Fragments of North Korean missiles have also been discovered in Ukraine.

Any arms trade with North Korea would violate several United Nations Security Council resolutions on North Korea regarding its nuclear weapons program, which Russia, a permanent council member, had previously supported. Both countries deny any arms transfers.

Andrei Lankov, an expert on North Korea at Kookmin University in Seoul, mentioned to The Associated Press news agency that in exchange for providing artillery munitions and short-range ballistic missiles, North Korea hopes to obtain more advanced weapons from Moscow.

Lankov noted that although Russia might be hesitant to share its top-tier military technologies with North Korea, it is keen on obtaining munitions from Pyongyang.

"In a war, there is never enough ammunition. The demand for them is immense," he said.

Recently, Russia has been eager to showcase the rejuvenated relationship with North Korea since the onset of the war in Ukraine, alarming the US and its allies in Europe and Asia.

Putin’s foreign policy advisor, Yuri Ushakov, mentioned that a partnership agreement addressing security issues could be signed during the visit.

He clarified that the agreement would not target any other country but would "outline future cooperation prospects and be signed considering recent developments in international politics, economics, and security issues."

Russian Defense Minister Andrei Belousov, Foreign Minister Sergey Lavrov, and Deputy Prime Minister Alexander Novak will accompany Putin on the trip.

Key meetings are set to occur on Wednesday, and satellite images suggest preparations for a military parade in central Pyongyang by North Korea.

After concluding his visit to Pyongyang, Putin will travel to Vietnam.