The defence ministry in Canberra said it has raised concerns with Beijing after the incident, which it said took place on Wednesday.

It said the frigate HMAS Toowoomba had been conducting "routine activities" in the Yellow Sea when its helicopter was intercepted by a Chinese aircraft.

"The PLA-N helicopter matched the ADF helicopter's altitude before closing in to an unsafe distance," it said, referring to China's People's Liberation Army Navy.

"The Chinese helicopter moved slightly ahead, increased speed and then rolled towards the ADF helicopter," the defence ministry said. The aircraft then took "evasive action to maintain safe flight".

"Australia expects all countries, including China, to operate their militaries in a safe and professional manner," it said.

Asked about the incident at a regular briefing on Friday, Beijing's foreign ministry said it was not aware of it and referred journalists to "the competent authorities".