A Chinese fighter aircraft dangerously intercepted an Australian military surveillance plane in the South China Sea region in May, Australia's defence department said on Sunday.
The Royal Australian Air Force P-8 maritime surveillance aircraft was intercepted by a Chinese J-16 fighter during "routine maritime surveillance activity" in international airspace in the region on May 26, defence said in a statement.
"The intercept resulted in a dangerous manoeuvre which posed a safety threat to the P-8 aircraft and its crew," it said.
Prime Minister Anthony Albanese told reporters in Perth that his government had expressed concerns to China "through appropriate channels".
China's foreign ministry in Beijing and its embassy in Australia did not respond to requests for comment outside business hours.
Defence Minister Richard Marles said the Chinese jet flew very close in front of the RAAF aircraft and released a "bundle of chaff" containing small pieces of aluminium that were ingested into the Australian aircraft's engine.
"Quite obviously this is very dangerous," Marles told ABC television.
Australia has previously joined the United States in stating that China’s claims around contested islands in the South China Sea do not comply with international law.
Defence said for decades it had undertaken maritime surveillance in the region and "does so in accordance with international law, exercising the right to freedom of navigation and overflight in international waters and airspace".
Relations between Australia and China, major trading partners, have been strained recently over growing Chinese influence in the Pacific after China sought a regional security deal with Pacific Island nations.
Also in May, a Chinese intelligence ship was tracked off Australia's west coast within 50 nautical miles of a sensitive defence facility, which is used by Australian, US and allied submarines.
In February, China and Australia traded barbs over an incident in which Australia said one of its maritime patrol aircraft detected a laser directed at it from a People's Liberation Army Navy vessel.
The Royal Australian Air Force P-8 maritime surveillance aircraft