SEOUL (Reuters) -North Korean leader Kim Jong Un praised "heroic" North Korean troops who fought for Russia in the war against Ukraine, in a meeting with officers of the army's overseas operation, state media KCNA said on Thursday.

North Korean leader Kim Jong Un said his country must quickly expand its nuclear arsenal as he warned that annual U.S.-South Korea military exercises included a "nuclear element" which he said could spark war, North Korean state media reported.

Kim Yo Jong's remarks fit a longstanding pattern of aggressive language during ongoing South Korea-U.S. military drills, which the North has long denounced as invasion rehearsals, but also reflect a shift in Pyongyang’s approach to its rival.