<span style="color: #222222;">Russia and North Korea will expand their comprehensive and constructive bilateral relations. In a letter sent to his counterpart Kim Jong-un on Pyongyang's liberation day, Mr. Putin said the move would be in both countries' interests.<br />''<br />''In turn, Mr. Kim said the friendship between both nations had been forged in World War Two with victory over Japan. He added that their "comradely friendship" would grow stronger. The Soviet Union was once a major communist ally of North Korea, offering economic cooperation, cultural exchanges and aid.</span><br />