UNITED NATIONS - China's permanent representative to the United Nations Li Baodong on Thursday met with UN Secretary-General Ban Ki-moon and filed a copy of the Chinese government's Diaoyu Islands baseline announcement with the United Nations.

China has now fulfilled all the obligations as stipulated in the UN Convention on the Law of the Sea (UNCLOS), and has completed the whole legal process regarding the announcement of the base points and baselines of the territorial waters of Diaoyu Islands and their affiliated islets.

Under article 16 of UNCLOS, coastal states are required to deposit with the UN chief charts showing straight baselines and archipelagic baselines as well as lists of geographical coordinates.

The Chinese Foreign Ministry issued a strongly worded statement on Monday after the Japanese government decided to "buy" part of China's Diaoyu Islands at a cabinet meeting.

In a move to demonstrate China's sovereignty over these islets, the Chinese government on Monday announced the base points and baselines of the territorial waters of Diaoyu Islands and their affiliated islets in accordance with its law on territorial seas and adjacent zones.

UNCLOS, dubbed as the Law of the Sea treaty, is an international agreement that resulted from the third UN Conference on the Law of the Sea.

The Convention defines the rights and responsibilities of nations in their use of the world's oceans, and establishes guidelines for businesses, the environment, and the management of marine natural resources.