BEIJING - Foreign Ministry spokesman Hong Lei on Thursday urged relevant countries to jointly safeguard peace and stability in the South China Sea.

It has been reported that the Philippines plans to build a simple wharf on Zhongye Island of the Nansha Islands.

Hong told a regular press conference that China owns "indisputable sovereignty" over the Nansha Islands and their adjacent waters.

China opposes any illegal activity that infringes upon its sovereignty over the islands, said the spokesman.

Relevant countries should comply with the Declaration on the Conduct of Parties in the South China Sea, and avoid taking any action to complicate disputes, he said.