The defense chiefs of South Korea and Japan held bilateral talks on Thursday and agreed on the importance of their bilateral cooperation as well as trilateral cooperation involving the United States in the face of evolving North Korean military threats, the South's defense ministry said.In the teleconference earlier in the day, Defense Minister Kim Yong-hyun congratulated his Japanese counterpart, Gen Nakatani, on his appointment and called for close communication to boost their defense exchange and cooperation, according to the ministry.In response, Nakatani noted the growing importance of their bilateral cooperation and exchange in the defense sector and expressed hope for further advancing such relations.In their meeting, both sides concurred that close cooperation between South Korea and Japan as well as the U.S. is "essential" as North Korea seeks to deepen military cooperation with Russia, the ministry said, adding the ministers agreed to meet in person to discuss key security issues.Thursday's teleconference marked their first talks since Nakatani took office as Japan's defense chief on Oct. 1.Source: Yonhap News Agency