The U.S. says there will be a "firm response" as Ukrainian forces holding ground in Russia's Kursk region now face North Korean troops "engaging in combat."

Russia has amassed a large force of tens of thousands — including recently arrived North Korean troops — to carry out an assault on the Ukrainian positions in Russia’s Kursk region expected in the coming days,

South Korean and US intelligence services have confirmed the participation of North Korean soldiers in hostilities in Russia, particularly in Kursk Oblast. Source: ISW Details: South Korea's National Intelligence Service reported on 13 November that North Korean troops were participating in hostilities in Russia,