If the information is correct, it would mark a significant increase in Russia's and North Korea's military cooperation, according to Sean Savett, spokesperson for the White House National Security Council.
"Such a move would also indicate a new level of desperation for Russia," says Savett in a statement.
On Tuesday, reports emerged that 18 North Korean soldiers had already deserted their positions in Russia, a few kilometers north of the border with Ukraine. Russian military is searching for the deserters, reports the Ukrainian public service company Suspilne, citing anonymous sources within the country's intelligence service.
Thousands of soldiers
According to sources for several Ukrainian media outlets, Russia is preparing a whole battalion, including North Korean soldiers, to be deployed in the Russian Kursk region, where Ukrainian forces are conducting an offensive. Kyiv Post reported on Tuesday that up to 3,000 North Koreans are expected to join the battalion.
The information has not been confirmed by independent parties.
Ukraine's President Volodymyr Zelenskyj warned on Sunday that North Korea is sending military personnel to Russia.
We see a growing alliance between Russia and regimes like North Korea. This is no longer just about delivering weapons. It's actually about transferring people from North Korea to the occupying military forces, he said in his evening speech.
Robots and grenades
Earlier this summer, Russia's President Vladimir Putin visited North Korea and signed a partnership agreement with the country's dictator Kim Jong-Un. On Monday, Putin according to Kyiv Post submitted a draft law to the Russian lower house, the State Duma, to ratify the agreement.
The agreement, among other things, stipulates that if either party is attacked or goes to war, the other will provide military assistance "in all possible ways".
North Korea has previously delivered significant quantities of weapons to Russia, including grenades and robots.