A Chinese spy ship has been detected off the Australian coast near joint war games underway between the United States, New Zealand and Australian militaries, the Australian Defence Force (ADF) said on Saturday.

The Chinese People’s Liberation Army-Navy Type 815 Dongdiao-class auxiliary general intelligence vessel was operating off the northeast coast during the Talisman Sabre war games, the ADF said in a statement.

The Chinese ship remained outside Australian territorial waters but was inside the Australian Exclusive Economic Zone in the Coral Sea, it said.

"The vessel’s presence has not detracted from the exercise objectives. Australia respects the rights of all states to exercise freedom of navigation in international waters in accordance with international law," the statement said.

More than 30,000 troops from the United States, New Zealand and Australia are taking part in biennial war games, which end in late July.

China's growing military presence, particularly in the disputed South China Sea, has raised tensions with regional neighbours and drawn criticism from both the United States and Australia.

Brunei, Malaysia, the Philippines, Vietnam and Taiwan also have claims in the South China Sea, through which about $5 trillion in ship-borne trade passes each year.