SYDNEY - U.S. soybean futures on Wednesday retreated from a more than two-month high hit in the previous session as some traders unwound positions, though recent Chinese purchases and lower-than-expected estimates for North American supplies capped losses.

The most active soybean futures on the Chicago Board Of Trade (CBOT) were down 0.3% at $9.16-3/4 a bushel by 0412 GMT. They rose 1.5% on Tuesday, when prices hit their highest since July 22 at $9.20 a bushel.

"There are some unwinding of positions weighing on prices," said Phin Ziebell, an agribusiness economist at National Australia.

"The outlook is uncertain, there are some Chinese purchases, but the U.S.-China trade talks are volatile."     Chinese firms purchased up to 600,000 tonnes of U.S. soybeans on Monday as part of a tariff-free quota allotted to importers to buy up to 2 million tonnes this week, two sources with knowledge of the deals said.

These deals offered some comfort to the market plagued by fears of a prolonged trade war between Washington and Beijing. Providing additional support to the market was a quarterly stocks report from the U.S. Department of Agriculture (USDA).

The USDA pegged U.S. soybean supplies at 913 million bushels as of Sept. 1, below the average estimate for 982 million bushels. Soy stocks, however, were up 108% from a year earlier, largely due to a drop in U.S. exports to China.

The most active corn futures were down 0.5% at $3.90-3/4 a bushel, having gained 1.2% in the previous session when prices hit their highest since mid-August at $3.92-3/4.

Like with soybeans, corn continued to be supported by the USDA's supply forecasts.

Corn stocks were at 2.114 billion bushels, the USDA said, below projections of 2.428 billion bushels and down 1% from a year ago. Wheat stocks were slightly above expectations at 2.385 billion bushels.

The most-active wheat futures were down 0.6% at $4.95-3/4 a bushel, having closed up 0.6% on Tuesday.    

(Reporting by Colin Packham; editing by Subhranshu Sahu)

© Reuters News 2019