SEOUL, June 19 - The new agreement between Russia and North Korea reached by their leaders at a Pyongyang summit requires both countries to use all available means to provide immediate military assistance in the event of war, North Korean state media said Thursday.

Both North Korea’s Kim Jong Un and Russia’s Vladimir Putin had described the deal reached Wednesday as a major upgrade of bilateral relations, covering security, trade, investment, cultural and humanitarian ties. Outside observers said it could mark the strongest connection between Moscow and Pyongyang since the end of the Cold War, The Associated Press reported.

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.”

The summit between Kim and Putin came as the U.S. 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.

The deal was made as Putin visited North Korea for the first time in 24 years, a visit that showcased their personal and geopolitical ties with Kim hugging Putin twice at the airport, their motorcade rolling past giant Russian flags and Putin portraits, and a welcoming ceremony at Pyongyang’s main square attended by what appeared to be tens of thousands of spectators.

According to KCNA, the agreement also states that Pyongyang and Moscow must not enter into agreements with third parties if they infringe on the “core interests” of another and must not participate in actions that threaten those interests.

Kim in recent months has made Russia his priority as he pushes a foreign policy aimed at expanding relations with countries confronting Washington, embracing the idea of a “new Cold War” and trying to display a united front in Putin’s broader conflicts with the West. (ap/ez)