Updates prices, adds quotes, changes byline, changes dateline from previous PARIS/SINGAPORE

By Julie Ingwersen

CHICAGO, March 4 (Reuters) - U.S. corn futures fell to their lowest levels in 2025 on Tuesday and soybean futures dropped below $10 a bushel on heightened concerns that President Donald Trump's trade policies will disrupt U.S. agricultural exports.

Trump slapped 25% tariffs on imports from Mexico and Canada and doubled duties on Chinese goods to 20%. Ottawa responded with 25% tariffs on more than $20 billion in U.S. imports while Beijing said it would impose additional tariffs on agricultural products starting next week. Mexico's government is expected to respond on Sunday.

"Retaliatory steps are beginning to emerge from these trading partners, raising fears of an ever-escalating trade war that will send our economy, and the global economy, into a recession, reducing demand for commodities in the process," StoneX chief commodities economist Arlan Suderman wrote in a client note.

As of 1:05 p.m. CST (1305 GMT), benchmark May corn futures on the Chicago Board of Trade CK25 were down 5-1/4 cents at $4.51 a bushel after hitting $4.42-1/2, the lowest on a continuous chart of the most-active contract Cv1 since Dec. 20.

CBOT May soybeans SK25 fell 14 cents to $9.97-1/2 a bushel and May wheat WK25 was down 11-3/4 cents at $5.36 a bushel after setting a life-of-contract low at $5.30.

Corn prices have plunged roughly 70 cents a bushel, about 14%, since mid-February as trade tensions and improving South American crop prospects prompted commodity funds to start unwinding a massive net long , or bought, position in corn futures.

"Funds were heavily extended to the long side, especially since the mid-January USDA reports. And with those positions now underwater, we're seeing losses in corn exacerbated by funds exiting those longs," said Randy Mittelstaedt, an analyst with R.J. O'Brien.

Some traders and analysts said short-term export flows to China may not be significantly altered, with an advancing Brazilian soybean harvest expected to absorb the bulk of Chinese demand in the coming months.

"China was not buying corn at all recently. Same for wheat. For soy, the current export window is for Brazil," a European trader said.

(Reporting by Julie Ingwersen; Additional reporting by Gus Trompiz in Paris and Naveen Thukral in Singapore; Editing by Richard Chang)

((Julie.ingwersen@thomsonreuters.com; 1-313-484-5283; Reuters Messaging: julie.ingwersen.thomsonreuters.com@reuters.net))