“As far as the details of that meeting and what will be discussed and when and where, I just don’t have any information to provide,” a spokesperson, Brig. Gen. Pat Ryder, told reporters.

“We remain concerned that North Korea is contemplating providing any type of ammunition or materiel support to Russia in support of their war against Ukraine,” he added.

The White House has repeatedly warned North Korea against making any arms deal with Russia, which would violate multiple United Nations Security Council resolutions. National security adviser Jake Sullivan said last week that North Korea would “pay a price” in the international community if it were to provide Russia with weapons.

State Department spokesperson Matthew Miller said Monday that the Biden administration would monitor any Putin-Kim meeting closely. He said the U.S. would continue to enforce sanctions against entities that fund Russia’s war effort “and will not hesitate to impose new sanctions if appropriate.”

Russia has been casting about for international support as it struggles against a Ukrainian counteroffensive, turning to fellow U.S. adversaries, including North Korea. Last month Kim and Putin exchanged letters pledging to increase their cooperation, according to U.S. officials and state media in both countries.

U.S. officials said last week that they expected Kim to travel to Russia and that arms talks were “actively advancing” and were likely to continue during Kim’s visit.

Experts say Russia would probably seek artillery munitions in exchange for providing energy and food aid to North Korea, where there are reports of starvation as Kim prioritizes his nuclear weapons and ballistic missile programs.

Kim may also want Russian assistance in advancing North Korea’s submarine, ballistic and satellite technologies, said Leif-Eric Easley, a professor at Ewha University in Seoul, South Korea. 

But Russia is unlikely to make such technology transfers, he said, “because even a desperate war machine does not trade its military crown jewels for old, dumb munitions.” 

He said the two countries would also avoid publicizing the full details of any arms deal “because of the serious international legal violations involved.”

Jennifer Jett reported from Hong Kong and Stella Kim from Seoul, South Korea.