By Jacob Bunge

CHICAGO--Grain and soybean futures fell Friday as traders mulled rising supplies and the potential for overseas trade in agricultural commodities to be roiled by the incoming Trump administration.

Soybean futures led the decline, which analysts also attributed to a slowdown in buying by investment managers, as well as farmers taking advantage of favorable prices by selling their crops.

Swelling stockpiles of U.S. crops have been front and center for farmers, grain traders and futures brokers this week after the U.S. Department of Agriculture boosted its estimates for record-breaking corn and soybean harvests this fall. The agency also raised its outlook for domestic corn stockpiles,pegging inventories at their highest in nearly three decades.

"We haven't dealt with this before," said Kurt Koester, president of Iowa-based grain brokerage AgriSource Inc.

January-dated soybean futures, the most actively traded oilseed contract at the Chicago Board of Trade, settled 1.2% lower at $9.86 a bushel on Friday. The contracts lost ground after earlier in the session rising because of a spike in palm oil futures traded in Asia, which were driven higher by a slide in the Malaysian currency and production problems.

Corn futures expiring in December fell 1% to settle at $3.40 1/4 a bushel, while December wheat declined 0.4% to close at $4.03.

Beyond Wednesday's bearish USDA report, grain markets have been buffeted this week by shifting views on the impact of Donald Trump's election to the U.S. presidency, and in particular his pledges to renegotiate trade deals.

Mr. Trump's criticisms of U.S. economic relationships with China and Mexico -- the respective first and third-largest buyers of U.S. agricultural commodities, according to J.P. Morgan Chase & Co. -- have fueled worries over trade battles that could slow overseas sales of U.S. crops when supplies are already high, and prices for farmers low.

"You talk to [farmers] on the phone and they're worried about China, and will we have trade issues with them," said Craig Turner, senior broker at Daniels Trading in Chicago.

Soybean futures lost some support as investment managers, who had bought contracts this week to close out longer-standing bets soybean prices would fall, slowed that activity, analysts said.

Traders also are already looking ahead to the harvest in Brazil, which some said kicks off early in about a month, as bringing more soybeans to the global market early next year at a price that could undercut U.S. oilseeds.

Write to Jacob Bunge at jacob.bunge@wsj.com

(END) Dow Jones NewswiresNovember 11, 2016 16:19 ET (21:19 GMT)

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