Grain growers have thrown their support behind Trade Minister Simon Birmingham escalating action against China.

Senator Birmingham said a final decision had not been made.

"But it is certainly our instinct that we ought to use all avenues available to defend the integrity of Australian producers," he told the ABC on Monday.

"Our grain growers, like our winemakers, aren't government subsidised. They don't dump their product on global markets below value."

Treasurer Josh Frydenberg said Australia's preference was to resolve the barley dispute faster than possible through the WTO.

"We would obviously like to work through bilaterally with China some of these challenging issues," he told Network Seven.

"But we also retain the option of going through multilateral forums as well."

The trade dispute with Beijing has spread to coal, with more than 60 vessels carrying at least $700 million worth of Australian coal stranded off the Chinese coast.

There are roughly 1000 seafarers aboard the vessels.

The bulk carriers have been anchored there for several weeks after being refused permission to dock and unload their cargo.

Resources Minister Keith Pitt refused to say how many vessels were floating off Chinese ports.

Chinese authorities have blamed environmental standards for the hold ups.

But Mr Pitt said Australian coal was among the highest quality in the world.

"I'd be very surprised if any of those standards were being breached," he told ABC radio.

He is working with Australian exporters to try and resolve the trade disruptions.

The various trade strikes come as diplomatic relations between Australia and China remain under heavy strain.

China is irate at Australia for demanding an inquiry into the origins of coronavirus, speaking out about human rights abuses, and cracking down on foreign investment and interference.

Australian Associated Press