With historical rights over the South China Sea, China is entitled to draw the baselines for measuring the territorial sea of the islands in the South China Sea. In fact, in September 1958 China issued the Declaration on the Territorial Sea, which states that China's territorial sea along the mainland and its coastal islands takes as its baseline the line composed of the straight lines connecting basepoints on the mainland coast and on the outermost of the coastal islands; and the water area extending 12 nautical miles outward from this baseline is China's territorial sea, and the water areas inside the baseline are China's inland waters, and no foreign vessels for military use and no foreign aircraft may enter China's territorial sea and the air space above it without the permission of the Chinese government.

In July 1973, in a working paper on the sea area within China's jurisdiction submitted to the UN Seabed Committee, Beijing suggested that an archipelago or an island chain consisting of islands close to each other be taken as a whole in defining the limits of the territorial sea around it. Article 3 of the Law of the People's Republic of China on the Territorial Sea and the Contiguous Zone, too, says that the method of straight baselines composed of all the straight lines joining the adjacent basepoints should be used to draw the baselines of China's territorial sea.

Given that, China has the right to take archipelagoes such as the Xisha Islands as an integral whole and use straight baselines to delimit its territorial sea and determine the limits of the contiguous zone, exclusive economic zone and continental shelf in accordance with the provisions of the UNCLOS applicable to other land territory.

Apart from sovereign rights, China also enjoys traditional fishing rights in certain areas within the exclusive zones or archipelagic waters of an adjacent state, and such rights should be recognized and respected as stipulated in the UNCLOS. For hundreds of years, Chinese people have engaged in fishing and other activities to exploit marine resources. With the rapid advancement in navigational technology in recent decades, such activities have expanded further within the nine-dotted line.

Even though some neighboring countries have earmarked exclusive fishing areas and/or incorporated areas that fall within China's nine-dash line into their exclusive economic zone, China is still entitled to its traditional fishing rights and should still have access to the surplus resources in certain areas within the exclusive economic zone of other countries. As Article 51 of the UNCLOS says, an archipelagic state shall recognize traditional fishing rights and other legitimate activities of the immediately adjacent neighboring states in certain areas falling within archipelagic waters.

Parties to the South China Sea disputes, the Philippines and Vietnam in particular, have repeatedly questioned China's historic title over the South China Sea and spared no effort to paint China as a violator of international laws. The truth is, the approach taken by China so far, including the release of the vertical map, to reaffirm its historic title and thus strengthen its sovereign claim over the South China Sea, does not go against its commitment to the UNCLOS.

The author is a professor of international law and marine law at the Party School of the Central Committee of the Communist Party of China.