The United States has raised alarms regarding the progressing arms negotiations between Russia and North Korea, the White House announced on Wednesday.

Speaking at a press briefing, White House national security spokesperson John Kirby divulged that Russian Defense Minister Sergei Shoigu had visited North Korea to urge Pyongyang to supply artillery ammunition to Russia.

Reports suggest that Russian President Vladimir Putin and North Korean leader Kim Jong Un exchanged letters affirming a desire to enhance cooperation.

U.S. intelligence further indicated that a subsequent delegation of Russian officials had travelled to Pyongyang after Shoigu’s visit.

Both the North Korean and Russian missions to the United Nations in New York have yet to respond to requests for comments on the matter.

The United States has previously cautioned that North Korea might increase arms provision to Russia, whose military intervention in Ukraine in February 2022 has been met with strong opposition from the U.S. and its European allies, with Moscow referring to it as a “special military operation.”

Earlier this month, the U.S. imposed sanctions on three entities allegedly involved in arms transactions between North Korea and Russia.

Kirby revealed that North Korea had reportedly delivered infantry rockets and missiles to Russia last year, leading to Moscow’s pursuit of additional armaments.

The spokesperson expressed ongoing concerns over North Korea potentially extending military assistance to Russia’s forces engaged in the conflict in Ukraine, based on “new information” indicating progress in these discussions.

According to Kirby, the proposed agreements entail Russia receiving munitions intended for use against Ukraine, and could also encompass raw materials contributing to Russia’s defence industrial capabilities.

Urging North Korea to cease its arms negotiations with Russia, Kirby emphasised the necessity for Pyongyang to uphold the commitments it has made against supplying or selling arms to Russia.

At the United Nations, U.S. Ambassador Linda Thomas-Greenfield issued a statement on behalf of the United States, Japan, South Korea, and the United Kingdom, asserting that any arms deals between Russia and North Korea would contravene U.N. Security Council resolutions.