Australia and close ally New Zealand have been monitoring three Chinese navy vessels -- a frigate, a cruiser and a supply tanker -- since they were spotted in international waters last week.

The Chinese ships broadcast a verbal live fire warning Friday that was picked up by commercial planes over the Tasman Sea between Australia and New Zealand, Canberra said.

"This was very disconcerting for the planes," which had to change course, Australian Defence Minister Richard Marles said hours after the incident.

China had abided by international law but did not follow best practice of giving 12-24 hours' notice, and Canberra had raised the lack of notice with Beijing, Marles said.

Australia's Department of Defence issued a statement late Friday saying any live firing by the People's Liberation Army-Navy (PLA-N) has "most likely ceased".

"No weapon firings were heard or seen, however, a floating surface firing target was deployed by the PLA-N and subsequently recovered."

Australian forces would monitor the Chinese ships while they remain near the country's "maritime approaches", the department said.

New Zealand is working with Australia to monitor the task force and it, too, has no confirmation live firing actually occurred, said the country's defence minister, Judith Collins.

Beijing described the manoeuvres as training exercises that were "safe, standard and professional" and in line with international law, without commenting on whether live ammunition was used.

- Tense encounters -

It was the latest in a string of tense encounters between China and Australia in the increasingly contested airspace and shipping lanes of the Asia-Pacific region.

Last week, Canberra rebuked Beijing for "unsafe" military conduct, accusing a Chinese fighter jet of dropping flares near an Australian air force plane patrolling the South China Sea.

A Chinese fighter jet was accused of intercepting an Australian Seahawk helicopter in international airspace in 2024, dropping flares across its flight path.

In 2023, a Chinese destroyer was accused of bombarding submerged Australian navy divers with sonar pulses in waters off Japan, causing minor injuries.

The Australian government says it respects the right of all states to pass through international waters and airspace.

The United States and its allies including Australia frequently cross through the 180-kilometre (112-mile) Taiwan Strait to reinforce its status as an international waterway, angering China, which claims jurisdiction over the waters.