* Australia barley imports already curbed due to drought
* Australian government say local barley gets no subsidies
* China probe could create more uncertainty in market
* Traders hold back on orders beyond mid-January (Updates throughout; adds Sydney to dateline, adds byline)
By Hallie Gu and Colin Packham
BEIJING/SYDNEY, Dec 21 (Reuters) - China's commerce ministry on Friday launched an anti-subsidy probe into Australian barley imports, ramping up pressure on suppliers and increasing uncertainty in the market after an anti-dumping probe announced last month.
The added trade measure came as relations between China and Australia remained tense over questions of influence in Pacific island nations, and followed renewed rapport between Beijing and Washington that led to a trade truce. Chamber of International Commerce has complained that barley was subsidized by the Australian government, allowing the grain to enter the Chinese market in large volumes at low prices, hurting domestic suppliers, according to a statement published on the website of China's Ministry of Commerce.
A severe drought this year, though, has cut Australia's grain output, boosted prices and already curbed barley shipments, traders and analysts said.
"The measure has more symbolic significance than actual impact, especially for the feed industry," said Cherry Zhang, a grains analyst with Shanghai JC Intelligence Co Ltd.
"Australian barley prices have lost their edge ... already. And now as the Sino-U.S. relation eases, we'll probably be able to buy sorghum, corn and other feed products from the U.S. in the future," she said.
Australia's Minister for Trade Simon Birmingham said in an emailed response to Reuters on China's probe: "Similar to the initial anti-dumping investigation, these are unsubstantiated claims and they will be rigorously defended."
"Our barley producers operate in a competitive global market and in an entirely commercial way, receiving no government subsidies or similar support," Birmingham said.
The trade probe - which goes into effect on Friday and usually lasts for one year - could create further uncertainty in the market. Traders are already holding back on orders for delivery beyond mid-January, when a 60-day protection period during the anti-dumping investigation is scheduled to finish. buyers are very reluctant to purchase barley from Australia for delivery beyond mid-January, when Beijing could impose tariffs," said one senior grains trader, who declined to be named as he was not authorized to talk to the media.
Australia is China's top supplier of barley, which is used both in brewing and livestock feed. It exported 6.48 million tonnes to China in 2017, worth about $1.5 billion and close to three-quarters of the 8.86 million tonnes of barley that Chinese importers took last year, according to Chinese customs. GRA/CN
Australia's chief commodity forecaster earlier this month said barley output will fall nearly 20 percent this year to 7.3 million tonnes, while its exports will drop to 5 million tonnes.
The year-long subsidy probe can be extended for up to six months, the commerce ministry statement said, and covers Australian barley shipments over the period October 2017-September 2018.