Australia confirmed yesterday it was "exploring options" for conducting joint naval patrols with Indonesia in the South China Sea.
In a move likely to irk Beijing, Australian Foreign Minister Julie Bishop indicated support for the potential exercises, saying they would help deliver "peace and stability in the region". She said the patrols would be designed to exercise the right to freedom of navigation but did not state whether they would travel within 12 nautical miles of contested islands claimed by China.
"We have agreed to explore options to increase maritime cooperation and of course that would include coordinated activities in the South China Sea and the Sulu Sea," Ms Bishop told ABC Radio.
"This is all consistent with our policy of exercising our right of freedom of navigation and that's in accordance with international law."
The joint patrols were raised by Indonesian Defence Minister Ryamizard Ryacudu last week during a meeting in Bali attended by his Australian counterpart, Ms Marise Payne, and Ms Bishop.
Indonesia, along with numerous countries across the region, has increasingly found itself at odds with China over Beijing's assertion of sovereignty over the bulk of the South China Sea.
This has included Indonesia's navy firing at Chinese fishing boats in territory claimed by Jakarta.
Australia has conducted air force patrols over China-claimed parts of the South China Sea and has signalled it will consider naval patrols near the disputed islands - a move reportedly supported by United States officials.
But there are concerns in Australia that patrols near contested islands could inflame tensions with China, its largest trading partner. China has repeatedly and strongly objected to Australia's support for US freedom of navigation patrols and last month urged Canberra to "speak and act cautiously" about the dispute.
The joint patrol proposal comes ahead of Indonesian President Joko Widodo's first state visit to Australia next week. He is expected to focus on boosting military and trade ties and is likely to include discussion of efforts to address China's growing territorial assertiveness.
Australia and Indonesia already conduct joint sea patrols to combat people-smuggling and illegal fishing. Australia's Border Force and the Indonesian Coast Guard have held joint patrols in the Timor Sea, but the two nations have not conducted such operations in the South China Sea.
An expert on Australia's relationship with China, Professor Michael Wesley, dean of the College of Asia and the Pacific at the Australian National University, backed the proposed Australia-Indonesia naval patrols, saying Canberra had adopted a "very pragmatic" decision to conduct operations in the South China Sea but not within the 12 nautical mile zone.
"(The decision) probably reflects a judgment that those 12 nautical mile patrols... probably don't achieve that much," he told ABC News.
"Yet we do have to make a very clear assertion of what we believe are the general rights of freedom of navigation. It is very much in our interest to encourage other nations in the region to do the same."
An arbitration court in the Hague ruled in July against China's territorial claims in the South China Sea after a case was brought by the Philippines. China has refused to recognise the ruling.
Ms Bishop said Australia and Indonesia would notify countries in the region before conducting any exercises.
"This is a regular part of what our navy does," she said.
"This is part of our engagement in the region and this is in accordance with Australia's right of freedom of navigation, including in the South China Sea."