"The threat to trade is a clear and present danger," Mr Galbraith said. "If the area becomes a no-go zone for whatever reason … that would mean diverting shipping away from the area, which would add drastically to fuel costs and freight times.

"Ultimately it would mean higher freight fees for consumers and business."

University of Sydney energy and security analyst Dr John Lee said China had used trade as a weapon in the past and could do so again. A spat with Japan had resulted in a temporary cancellation of the rare earths trade.

"In Australia's case China might well threaten to do the same, though follow through might be more difficult because of the nature and structure of our trade," Dr Lee said.

"China might impose some regulatory burdens on Australian suppliers in some way … but it would be designed more to create political apprehension rather than economic or trade loss," he said.

Zeng Jinrun, a columnist published by the Hawkish Global Times website, said Australia would pay a "dear price" for siding with the United States.

"If an Australian aircraft arrives as planned, China should use Russia as an example and take bold action and send our military aircraft to drive it away," Mr Zeng wrote in an editorial. "If this does not work we should just shoot it down."

The US and Australia have been ramping up pressure on China to desist from land reclamation and militarisation of the disputed islands.


Defence Minister Kevin Andrews has flagged stepping up Australian warship and aircraft patrols in the area despite China repeatedly warning a US Navy P-8 to leave airspace near the disputed Spratly Islands while the American aircraft was on a similar mission last week.

University of Woollongong ocean resources and security analyst Dr Sam Bateman said a Chinese warship had challenged three Royal Australian Navy warships in the Taiwan Strait in 2001, some two weeks after a Chinese fighter jet collided with an American spy plane.

"China hasn't made clear what restrictions on navigation and overflight its imposing … when and if it does a diplomatic protest by Australia would be more appropriate, then jumping the gun and flying aircraft in to a messy legal situation," he wrote in an Australian Strategic Policy Institute blog.

"As well as provoking China that gesture would be seen by the region as Australia simply acting once again as a "deputy sheriff" to the US in the region," he said.

Former Prime Minister Bob Hawke urged the US and China to step up their dialogue to avoid any miscalculation over the South China Sea.

"It will be a great hope that China will issue the invitation and their can be joint development of the resources of the region … that's our best hope," he said.

Prime Minister Tony Abbott has maintained Australia's strong stance against China's actions warning Australia "deplores" attempt by any nation to expand its territory in the disputed region vowing Australia would "do whatever we can to uphold freedom of navigation on the sea and in the air".