Russian President Vladimir Putin hailed North Korean troops sent to fight in Ukraine as "heroic" in a letter to Kim Jong Un, North Korean state media reported Friday.- 'Excellent soldiers' - The letter from Putin came alongside a visit by a Russian delegation to Pyongyang,

North Korean leader Kim Jong-un told Russian President Vladimir Putin that their bilateral relations have reached "full bloom" and will advance more solidly in the future, according to the North's state media on Friday.

Russian State Duma Chairman Vyacheslav Volodin met with North Korean leader Kim Jong Un during an official visit to Pyongyang, the Russian parliament said on Thursday.