The Defense Ministers of South Korea, the United States and Japan signed a document on the Trilateral Security Cooperation Framework (TSCF), on Sunday, in a move solidifying their continued commitment to three-way security cooperation against North Korean threats.South Korean Defense Minister Shin Won-sik and his US and Japanese counterparts, Lloyd Austin and Minoru Kihara, respectively, inked a Memorandum of Cooperation on the framework in Tokyo amid their deepening security cooperation in response to the North's persistent and growing nuclear and missile threats.As the first document that institutionalizes joint efforts for trilateral security cooperation among defense authorities, it provides the direction and policy principle for areas of high-level policy consultations, information sharing and trilateral drills, according to the Korean defense ministry.