Seoul. South Korea said Thursday that it would consider sending arms to Ukraine, a major policy change suggested after Russia and North Korea rattled the region and beyond by signing a pact to come to each other’s defense in the event of war.

The comments from a senior presidential official came hours after North Korea’s state media released the details of the agreement, which observers said could mark the strongest connection between Moscow and Pyongyang since the end of the Cold War. It comes at a time when Russia faces growing isolation over its war in Ukraine and both countries face escalating standoffs with the West.

According to the text of the deal published by the North’s official Korean Central News Agency, if either country 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.” But the agreement also says that such actions must be in accordance with the laws of both countries and Article 51 of the United Nations Charter, which recognizes a UN member state’s right to self-defense.

North Korean leader Kim Jong Un and Russian President Vladimir Putin signed the pact at a summit Wednesday in Pyongyang. Both described it as a major upgrade of bilateral relations, covering security, trade, investment, cultural and humanitarian ties.

The office of South Korean President Yoon Suk Yeol issued a statement condemning the agreement, calling it a threat to the South’s security and a violation of UN Security Council resolutions, and warned that it would have negative consequences on Seoul’s relations with Moscow.

“It’s absurd that two parties with a history of launching wars of invasion -- the Korean War and the war in Ukraine -- are now vowing mutual military cooperation on the premise of a preemptive attack by the international community that will never happen,” Yoon’s office said.

Yoon’s national security adviser, Chang Ho-jin, said Seoul would reconsider the issue of providing arms to Ukraine to help the country fight off Russia’s invasion.

South Korea, a growing arms exporter with a well-equipped military backed by the United States, has provided humanitarian aid and other support to Ukraine while joining US-led economic sanctions against Moscow. But it has not directly provided arms to Kyiv, citing a longstanding policy of not supplying weapons to countries actively engaged in conflict.

The summit between Kim and Putin came as the US and its allies expressed growing concern 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.

Following their summit, 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, which 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