China's President Xi Jinping has promised to safeguard freedom of navigation in the South China Sea, where tensions have flared over overlapping claims and the U.S. Navy's moves to challenge Beijing's massive island building.

Speaking at the Institute of Southeast Asian Studies at the National University of Singapore, Xi said Saturday that there has never been any problem with freedom of navigation and overflight and "nor will there ever be in the future."

He says China needs unimpeded passage through the waters more than anyone else.

He says: "We have absolute confidence and capability in maintaining the peace and stability. This can be done through negotiations and the establishment of reasonable maritime rights."