China on Tuesday again expressed opposition to the tourist activities to the Nansha islands organized by Vietnam, calling it an infringement on China's territorial sovereignty.

Chinese Foreign Ministry spokesman Kong Quan said at a regular press conference here Tuesday that China has expressed repeated concern and opposition to the Vietnamese moves. On April 16, Chinese Vice Foreign Minister Wang Yi lodged strong representations over the issue in his meeting with Vietnamese Ambassador to China Tran Van Luat.

"China has said in unmistakable phrasing that it has indisputable sovereignty over the Nansha islands and the surrounding waters," Kong said. "The Vietnamese side has infringed on China's sovereignty and China firmly opposes it."

Kong said Vietnam has broken its commitments set forth in the Declaration on the Conduct of Parties in the South China Sea between China and the Association of Southeastern Asian Nations (ASEAN).

"We urge the Vietnamese side to honor its commitments and immediately stop taking any action that may further complicate the situation," Kong said.