* Soybeans flat after Wednesday's near 3-month top
* Traders await U.S. yield estimates after spring flooding
* USDA confirms China buys U.S. soybeans (Adds U.S. trading, updates market details, changes dateline from PARIS)
CHICAGO, Oct 10 (Reuters) - U.S. grain and soybean futures took a breather on Thursday after climbing to multi-month highs the previous session, as traders waited for a highly anticipated government crop report.
The U.S. Department of Agriculture, in its monthly World Agricultural Supply and Demand Estimates (WASDE) report, is expected to peg soybean yields at 47.3 bushels per acre, down from 47.9 bushels in September, according to a Reuters poll. Corn yields are expected to decline to 167.5 bushels from 168.2 bushels.
The agency is also expected to reduce its soybean and corn ending stocks estimates from last month.
Analysts and traders are uncertain about supplies after historic rains and flooding caused severe planting delays in the spring. Now, some are worried about a cold snap expected in the U.S. Midwest this weekend.
"The trade is anticipating that the WASDE report has the potential to lower bean yields a bit," said Tomm Pfitzenmaier, analyst for Summit Commodity Brokerage in Iowa.
"When you add in possible weather loss and the drop in the quarterly stocks, all of a sudden the burdensome soybean stocks we have been dealing with for a while now are not so burdensome."
The most-active soybean contract on the Chicago Board Of Trade (CBOT) was flat at $9.23-3/4 a bushel by 10:30 a.m CDT (1530 GMT), having climbed to its highest level since July 15 at 9.31-1/2 on Wednesday.
CBOT corn was down 0.8% at $3.91 a bushel, near a two-month high of $3.97-1/4 reached on Wednesday.
CBOT wheat slipped 0.1% to $4.99-3/4 after prices reached a two-month high of $5.04-1/2 on Wednesday.
The USDA, in a daily reporting system for export sales, said China bought 398,000 tonnes of U.S. soybeans. The agency, in another report, said total soybean export sales were 2.096 million tonnes from Sept. 27 to Oct. 3, topping forecasts for 1.3 million tonnes to 1.8 million tonnes.
Traders are focused on China's soybean demand as Washington and Beijing seek to resolve the bruising trade war that has slowed exports of U.S. farm products including soybeans.
The United States' and China's top trade negotiators were set to meet on Thursday for the first time since late July to try to find a way out of the 15-month dispute.
(Reporting by Tom Polansek in Chicago Additional reporting by Gus Trompiz in Paris and Naveen Thukral in Singapore Editing by Jane Merriman and Matthew Lewis)