North Korean leader Kim Jong Un praised what he called the “unmatched courage” of his country’s troops fighting alongside Russian forces against Ukraine, during a visit to a memorial site being built for victims of the war, the Korean Central News Agency reported.

KCNA quoted Kim as saying on Friday during an inspection of the site: “The unmatched courage and heroism displayed by soldiers of the Korean People’s Army participating in overseas military operations must be etched in history as a symbol of invincible strength.”

Russia’s ambassador to North Korea attended a foundation-laying ceremony in October for what was described as a “Memorial Museum of Combat Feats,” at which Kim said relations with Moscow had reached a “historic peak.”

There was no immediate comment from Ukraine or Russia on Kim’s remarks.