South Korea and China agreed Friday to strengthen their cooperation efforts to denuclearize North Korea, reiterating their commitment to resolving the issue, South Korean foreign ministry said.The two sides reached the agreement during talks in Seoul between South Korean Deputy Foreign Minister Lee Kyung-soo and Chinese Vice Foreign Minister Liu Zhenmin, a foreign ministry official said.“South Korea and China confirmed again their firm, shared recognition of the goal of not allowing and getting rid of North Korea’s nuclear weapons program while also agreeing to further step up collaboration to make substantial progress on the North Korean nuclear issue,” an unnamed ministry official was quoted as saying by South Korean news agency Yonhap.The Chinese official also briefed his South Korean counterpart on details of his latest visit to Pyongyang. He stressed in his meeting with North Korean officials that Pyongyang needs to take steps toward denuclearization before the long-stalled six-party talks can resume, according to the ministry official.