China on Saturday dismissed Japan's claim of UN backing in its extension of continental shelf, saying that Japan's claim was baseless.

Japanese media reported that Japanese government officials on Saturday welcomed the backing of the UN Commission on the Limits of the Continental Shelf for the country's claim that the seabed north of the Okinotori atoll is part of its continental shelf.

"The UN Commission on the Limits of the Continental Shelf has not announced its decision concerning the case of the outer limits of Japan's continental shelf. I don't know on what grounds did Japan make such a claim," Liu said, adding that international mainstream views do not support Japan's claim.

China insists that according to the international law, the Okinotori atoll shall have no exclusive economic zone or continental shelf, Liu said.

The Okinotori atoll, some 1,700 kilometers south of Tokyo, is only about 10 square meters above the sea at the flood-tide.

According to Article 121 of the United Nations Convention on the Law of the Sea, rocks that cannot sustain human habitation or an economic life of their own shall have no exclusive economic zone or continental shelf.