CHINA said it conducted air and sea drills in the South China Sea as it stakes an increasingly assertive claim to virtually the whole sea despite rival claims by neighbours, Reuters reports.

The live-ammunition drills involved more than 100 ships, dozens of aircraft, information warfare units as well as the nuclear force, the state-backed China Military Online said.

It did not specify where exactly the exercises took place.

Beijing claims most of the energy-rich South China Sea, through which US$5 trillion in shipborne trade passes every year, and rejects the rival claims of Vietnam, the Philippines, Brunei, Malaysia and Taiwan.

The United States has called on claimants to settle differences through talks and has said its Pacific Fleet aims to protect sea lanes critical to US trade with Southeast Asia and the oil-rich Middle East.

The latest exercises focused on integrating information warfare systems with air and naval forces, as well as testing the combat effectiveness of new weapons and equipment, China Military Online said.

The exercises were conducted in "a complex electromagnetic environment" involving many types of missiles, torpedoes, shells and bombs.