Russian President Vladimir Putin will arrive in North Korea on Tuesday for a two-day visit, his first in 24 years, both countries announced.

Putin is expected to meet North Korean leader Kim Jong Un for talks focused on expanding military cooperation as they deepen their alignment in the face of separate, intensifying confrontations with Washington.

North Korea’s official Korean Central News Agency said Monday that Putin will pay a state visit to the North on Tuesday and Wednesday at the invitation of Kim. North Korean state media didn’t immediately provide more details. Russia confirmed the visit in a simultaneous announcement.

The visit comes amid growing international concerns about an arms arrangement in which Pyongyang provides Moscow with badly needed munitions to fuel Putin’s war in Ukraine in exchange for economic assistance and technology transfers that would enhance the threat posed by Kim’s nuclear weapons and missile program.

Military, economic and other cooperation between North Korea and Russia have sharply increased since Kim visited the Russian Far East in September for a meeting with Putin, their first since 2019.

U.S. and South Korean officials have accused the North of providing Russia with artillery, missiles and other military equipment to help prolong its fighting in Ukraine, possibly in return for key military technologies and aid.

U.S. and South Korean officials have accused the North of providing Russia with artillery, missiles and other military equipment to help prolong its fighting in Ukraine, possibly in return for key military technologies and aid. Both Pyongyang and Moscow have denied accusations about North Korean weapons transfers, which would be in violation of U.N. Security Council resolutions.

Any weapons trade with North Korea would be a violation of multiple U.N. Security Council resolutions that Russia, a permanent U.N. Security Council member, previously endorsed.

Andrei Lankov, an expert on North Korea at Kookmin University in Seoul, noted that in exchange for providing artillery munitions and short-range ballistic missiles, Pyongyang hopes to get higher-end weapons from Moscow.

Lankov noted that while Russia could be reluctant to share its state-of-the-art military technologies with North Korea, it’s eager to receive munitions from Pyongyang. “There is never enough ammunition in a war, there is a great demand for them,” Lankov told The Associated Press.

Putin first visited Pyongyang in July 2000, months after his first election when he met with Kim’s father, Kim Jong Il, who ruled the country then.

Moscow has said it “highly appreciates” Pyongyang’s support for Russia’s military action in Ukraine and mentioned its “close and fruitful cooperation” at the United Nations and other international organizations.

Russia, together with China, have repeatedly blocked the U.S. and its partners’ attempts to impose fresh U.N. sanctions on North Korea over its barrage of banned ballistic missile tests.

In March, a Russian veto at the United Nations ended monitoring of U.N. sanctions against North Korea over its nuclear program, prompting Western accusations that Moscow is seeking to avoid scrutiny as it allegedly violates the sanctions to buy weapons from Pyongyang for use in Ukraine.

Earlier this year, Putin sent Kim a high-end Aurus Senat limousine, which he had shown to the North Korean leader when they met for a summit in September. Observers said the shipment violated a U.N. resolution aimed at pressuring the North to give up its nuclear weapons program by banning the supply of luxury items to North Korea.

Putin has continuously sought to rebuild ties with Pyongyang as part of his efforts to restore his country’s global clout and its Soviet-era alliances. Moscow’s ties with North Korea weakened after the 1991 Soviet collapse. Kim Jong Un first met with Putin in 2019 in Russia’s eastern port of Vladivostok.