A naval survey team and civilian engineers have finished building a lighthouse at Waikejiao, 33 00.9' N and 121 38.4' E, the last of 13 permanent facilities built to mark the country's East China Sea territorial baseline, according to an officer with the People's Liberation Army (PLA) Navy's East Sea Fleet.

Captain Zou Xingguo, political commissar of the Navy's survey team, said the permanent facilities and data collection at the base points will clarify where China's territorial waters begins and provide substantial legal basis for China's claim.

China joined the UN Convention on the Law of the Sea in 1996 and claims 12 nautical-mile wide territorial sea adjacent to the country's mainland, Taiwan and other major islands.

Also in 1996, China declared its first offshore base points from the mainland and the Xisha Islands. Straight lines joining these base points shall be a part of the baseline of the territorial sea adjacent to the mainland and the Xisha Islands, according to the Law on the Territorial Sea and the Continuous Zone.

China has settled land boundary disputes with 12 neighboring countries through negotiation, accounting for about 90 percent of its total borderline, according to National Land and Sea Defense Commission.

But disagreements with neighboring countries over territorial waters remain unresolved.

Japan regards China's Diaoyu Islands in the East China Sea as it territory. The two countries also hold disputes on overlapping claims of their extended continental shelf in the East China Sea where both countries have oil-drilling platforms.

The Ministry of Foreign Affairs says China has indisputable sovereignty over the Diaoyu Islands and adjacent islets, an inalienable part of China's territory since ancient times.

The ministry opposed Japan's 2008 bid in the UN to extend its continental shelf.

China has protested the Philippines' 2009 law that designates China's Huangyan Island and some of the Nansha Islands as Philippine territory.

In another dispute, Vietnam still claims sovereignty over China's Xisha Islands, or Paracel Islands, in the South China Sea.