Australia sends veiled warning to China
Australia has expressed support for the United States' naval patrol challenging China's dubious territorial claims over artificial islands in the South China Sea but stressed it had no part in the operation. 
Defence Minister Marise Payne said in a statement on Tuesday afternoon that Australia had a keen interest in ensuring shipping was unimpeded in the contested waters, given 60 per cent of Australian exports passed through the area.
"It is important to recognise that all states have a right under international law to freedom of navigation and freedom of overflight, including in the South China Sea. Australia strongly supports these rights," Senator Payne said.
She added: "Australia is not involved in the current United States activity in the South China Sea."
However, leaving the door open on the possibility of future Australian involvement, Senator Payne said: "Australia continues to co-operate closely with the United States and other regional partners on maritime security."
She was speaking after Pentagon officials confirmed that a US destroyer, the Lassen, had sailed on Tuesday close to the Subi and Mischief reefs in the Spratly archipelago, territory claimed by Beijing.
The patrol marked the first time a US naval ship has passed within 12 nautical miles - the maritime territorial zone defined by international law - of such Chinese-claimed territory since 2012.
Fairfax Media reported in   May that defence planners were considering involving the Royal Australian Navy in such "freedom of navigation" exercises, either alone or as part of a joint patrol with the US and other countries in the region.
But it is understood that ultimately the Australian Defence Force was not asked to take part by Washington, with the Americans apparently deciding it would be simpler and less risky to do it on their own.
Successive governments in Canberra have said they take no sides in the maritime disputes in Asian waters but oppose unilateral moves such as China's recent island-building, which has progressed at a furious pace.
The land reclamation has included the construction of runways and ports, allowing the islands to be militarised if needed.
Senator Payne told a high-powered naval conference in Sydney this month that Australia "continues to strongly oppose the use of intimidation, of aggression or coercion to advance any country's claims or to unilaterally alter the status quo" - a clear reference to China's behaviour.
China is locked in disputes with several neighbours over maritime territorial claims in the South China Sea including Malaysia, the Philippines and Vietnam.
To bolster its claims, Beijing has been building up reefs and rocks that would not normally sit above high tide and therefore are not recognised as territory under international law.
While other countries have in the past also undertaken such land reclamation, those efforts have been dwarfed by China's recent activity.
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