The world's navies must work together to combat threats such as terrorism and piracy, China's People's Liberation Army (PLA) Navy Commander Admiral Wu Shengli said Tuesday.

Wu said at a meeting of international naval officials that terrorism, separatism, extremism, piracy and transnational crimes, such as smuggling, posed serious challenges to the maritime peace and safety.

It was the obligation of all countries' naval forces to work together to ensure safety on the oceans, and crack down on such unconventional threats, Wu said.

However, he said, such obligations should only be carried out under the guidance of the United Nations.

"We must abide by the principles and the regulations of the United Nations Charter when handling maritime affairs and carrying out military operations on the oceans," he said.

Governments should respect each other's sovereignty and territorial integrity on an equal and mutually beneficial basis, and should not use, or threaten to use military force in international relations, Wu urged.

He said maritime disputes should be resolved through equal consultation and negotiation in accordance with the United Nations Convention on the Law of the Sea, and all countries should avoid military competition or conflict.

Exchanges and cooperation between naval forces of different countries would enhance mutual trust and development, he said.

All countries should also strive to protect the ocean environment, Wu told a seminar attended by senior naval officials from around the world to mark the 60th anniversary of the founding of the PLA Navy.

China launched a grand maritime ceremony to mark the 60th anniversary of the founding of its navy on Monday off the coast of the eastern city of Qingdao.

The four-day celebration includes seminars, a sampan race and a fleet review scheduled for Thursday that will feature the first public appearance of the country's nuclear submarines.

A total of 21 foreign naval vessels from 14 countries, including the United States and Russia, and delegations from 29 countries will take part.

The PLA Navy was founded on April 23, 1949, with nine warships and 17 boats obtained when a unit of the Kuomintang's second coastal defense fleet defected to the PLA.

(Xinhua News Agency April 21, 2009)