A top Chinese official made a previously unannounced visit to South Korea on Saturday and held talks with Seoul's Foreign Minister Kim Sung-hwan, an official said, amid high tensions over North Korea's deadly artillery strike on a South Korean island earlier this week.

   Chinese State Councilor Dai Bingguo, who traveled together with Beijing's chief nuclear negotiator Wu Dawei, discussed Tuesday's attack and six-nation talks on ending Pyongyang's nuclear programs during a dinner meeting with Kim, the foreign ministry official said on condition of anonymity.

   Dai's trip came a day before South Korea and the United States are set to launch massive naval exercises in the Yellow Sea in response to the North's bloody shelling Tuesday of the South's Yeonpyeong Island, which killed four people, including two civilians, and wounded 18 others.

   China has expressed concern about the maneuvers that will involve the U.S. aircraft carrier USS George Washington.

   Beijing is very sensitive about such drills in waters close to its territory, and strongly protested earlier this year when Seoul and Washington announced massive anti-submarine exercise plans in response to North Korea's sinking of a South Korean warship in March. (Yonhap News)