North Korea sends foreign minister to Russia as its troops train to fight in Ukraine

North Korea said Tuesday its top diplomat is visiting Russia, in another sign of their deepening relations as rival South Korea and Western nations say the North has sent thousands of troops to support Russia's war in Ukraine.

North Korea's official Korean Central News Agency said a delegation led by Foreign Minister Choe Son Hui departed for Russia on Monday, but didn't specify the purpose of the visit.

In a closed-door hearing at South Korea's parliament, the South's spy agency said Choe may be involved in high-level discussions on sending additional troops to Russia and negotiating what the North would get in return, according to Lee Seong-kweun, a lawmaker who attended the meeting.

The announcement of Choe's visit came hours after the Pentagon said North Korea has sent about 10,000 troops to Russia, who are expected to arrive in battlefields in Ukraine within “the next several weeks.” South Korean and Western leaders have expressed concern that North Korean involvement could help prolong Russia's aggression in Ukraine, and that Russia may offer technology in return that could advance the threat posed by North Korea's nuclear weapons and missile programme.

Pentagon spokesperson Sabrina Singh told reporters Monday that some of the North Korean soldiers have already moved closer to Ukraine and were believed to be heading for the Kursk border region, where Russia has been struggling to push back a Ukrainian incursion.

South Korea's National Intelligence Service told lawmakers it's examining the possibility that some groups of North Korea's military personnel in Russia, including generals or other high-ranking officials, may have already moved to frontline areas. The spy agency also said to appear to be struggling to resolve communication issues although the Russian military is training North Korean troops on Russian military terminology, Lee said.

The agency said space-based reconnaissance is an area where North Korea is likely receiving Russian help. It said North Korea may be acquiring advanced components from Russia as it prepares to launch another military reconnaissance satellite following a failed attempt in May, said Park Sun-won, another lawmaker who attended the hearing.

North Korea first placed a spy satellite in orbit last November. Its leader Kim Jong Un has described those assets as crucial for monitoring South Korean and US military activities and enhancing the threat of his nuclear-capable missiles.

South Korean President Yoon Suk Yeol in telephone calls with European Union Commission President Ursula von der Leyen and NATO Secretary-General Mark Rutte on Monday shared South Korean intelligence assessments that North Korean troops could be deployed to battlefronts “more quickly than anticipated.” He called for closer coordination with European governments aimed at “monitoring and blocking “illegal exchanges between Pyongyang and Moscow, Yoon's office said in a statement.

After initially denying the claims about North Korean troop deployments, Pyongyang and Moscow have adopted a vaguer stance, asserting that their military cooperation conforms with international law without directly admitting the presence of North Korean forces in Russia.

North Korea has also been accused of providing millions of artillery shells and other military equipment to Russia to fuel its war in Ukraine. The United States and its partners have described Russia's procurement of North Korean personnel and supplies as a violation of UN Security Council resolutions, and raised suspicions that Moscow is helping Pyongyang to evade sanctions and unlawfully finance its weapons programme.

Russia, along with China, has blocked US-led efforts at the Security Council to tighten sanctions on North Korea over its recent missile testing activities. Russia also vetoed a UN resolution to extend the mandate of a panel of monitors in March in a move that effectively abolished oversight by UN experts of Security Council sanctions against North Korea. It prompted Western accusations that Moscow was acting to shield its arms purchases from Pyongyang.

“The illegal military collusion between Russia and North Korea poses a significant security threat to the international community and a serious matter that could potentially harm our security. We must thoroughly examine all possibilities and prepare countermeasures,” Yoon said in a Cabinet meeting in Seoul on Tuesday.

Yoon last week raised the possibility of supplying Ukraine with weapons while saying Seoul is preparing countermeasures that could be rolled out in stages depending on the degree of military cooperation between Pyongyang and Moscow.

South Korea, a growing arms exporter, has provided humanitarian aid and other non-lethal support to Ukraine and joined US-led economic sanctions against Moscow. It has so far resisted calls by Kyiv and NATO to directly supply Ukraine with weapons, citing a longstanding policy of not providing arms to countries engaged in active conflict.