Russia and North Korea sign partnership deal that appears to be the strongest since the Cold War

HANOI, Vietnam — Russian President Vladimir Putin and North Korean leader Kim Jong Un signed an agreement Wednesday that pledges mutual aid if either country faces "aggression," a strategic pact that comes as both face escalating standoffs with the West.

Details of the deal were not immediately clear, but it could mark the strongest connection between Moscow and Pyongyang since the end of the Cold War. Both leaders described it as a major upgrade of their relations, covering security, trade, investment, cultural and humanitarian ties.

The summit came as Putin visited North Korea for the first time in 24 years and the U.S. and its allies expressed growing concerns over a possible arms arrangement in which Pyongyang provides Moscow with badly needed munitions for its war in Ukraine in exchange for economic assistance and technology transfers that could enhance the threat posed by Kim's nuclear weapons and missile program.

From North Korea, Putin traveled to Vietnam. In Hanoi, Putin was scheduled to meet with Vietnam’s most powerful politician, Communist Party General Secretary Nguyen Phu Trong, and new President To Lam, as the Russian leader seeks to strengthen ties with a longtime partner.

During Putin's visit to North Korea, Kim said the two countries had a "fiery friendship," and that the deal was their "strongest ever treaty," putting the relationship at the level of an alliance. He vowed full support for Russia's war in Ukraine.

Putin called it a "breakthrough document" reflecting shared desires to move relations to a higher level.

North Korea and the former Soviet Union signed a treaty in 1961 that experts say necessitated Moscow's military intervention if the North came under attack. The deal was discarded after the collapse of the USSR, replaced by one in 2000 that offered weaker security assurances.

The North’s official Korean Central News Agency on Thursday reported the language of the comprehensive strategic partnership agreement. The agency said Article 4 of the agreement states that if one of the countries gets invaded and is pushed into a state of war, the other must deploy “all means at its disposal without delay” to provide “military and other assistance.”

Kim met Putin at the airport, where the two shook hands, hugged twice and rode together in a limousine. The huge motorcade rolled through the capital's brightly lit streets, where buildings were decorated with giant Russian flags and portraits of Putin.

After spending the night at a state guest house, Putin was welcomed Wednesday morning in a ceremony at the city's main square, filled with what appeared to be tens of thousands of spectators, including children with balloons and people in coordinated T-shirts of the red, white and blue national colors of both countries. Crowds lining the streets chanted "Welcome Putin," and waved flowers and flags.

Putin and Kim saluted an honor guard and walked across a red carpet. Kim introduced key members of his leadership, including Foreign Minister Choe Son Hui; top aide and ruling party secretary Jo Yong Won; and the leader's powerful sister, Kim Yo Jong.

At their talks, Putin thanked Kim for North Korea's support in Ukraine, part of what he said was a "fight against the imperialist hegemonistic policies of the U.S. and its satellites against the Russian Federation."

Putin praised ties that he traced to the Soviet army fighting the Japanese military on the Korean Peninsula at the end of World War II, and Moscow's support for Pyongyang during the Korean War.

What kind of support was pledged in the agreement was not spelled out. Explanations of the agreement by the leaders did not specify what the "mutual assistance" would be in the event of aggression against either country — troops, materiel or some other sort of aid.

Kim has used similar language before, consistently saying North Korea supports what he describes as a just action to protect Russia's interests and blaming the crisis on the West's "hegemonic policy."

North Korea is under heavy U.N. Security Council sanctions over its weapons program, while Russia also faces sanctions by the U.S. and its Western partners over its invasion of Ukraine.

U.S. and South Korean officials accuse the North of providing Russia with artillery, missiles and other military equipment for use in Ukraine, possibly in return for key military technologies and aid.

On Tuesday, a U.S. State Department spokesman said that in recent months, Washington has seen North Korea "unlawfully transfer dozens of ballistic missiles and over 11,000 containers of munitions to aid Russia's war effort."

Both Pyongyang and Moscow deny accusations of weapons transfers, which would violate multiple U.N. Security Council sanctions that Russia previously endorsed.

Along with China, Russia has provided political cover for Kim's efforts to advance his nuclear arsenal, repeatedly blocking U.S.-led efforts to impose fresh U.N. sanctions on the North over its weapons tests.

In Washington, U.S. Secretary of State Antony Blinken said Putin's visit illustrates how Russia tries, "in desperation, to develop and to strengthen relations with countries that can provide it with what it needs to continue the war of aggression that it started against Ukraine."