BEIJING, June 24 (Reuters) - Chicago corn and wheat futures declined for a fourth session on Wednesday, as investors weighed developments in U.S.-Iran peace discussions and kept a close watch on U.S. weather conditions.

Soybeans edged higher as traders assessed signs of bulk purchases from top importer China.

FUNDAMENTALS

* The most-active soybean contract on the Chicago Board of Trade (CBOT) Sv1 was up 0.18% at $11.43-3/4 a bushel, as of 0112 GMT, while corn Cv1 edged 0.06% lower to $4.09-1/2 a bushel. Wheat Wv1 fell 0.21% to $5.95-3/4 a bushel.

* The U.S. winter wheat harvest was 40% complete, the U.S. Department of Agriculture said in a weekly report on Monday. That exceeded analysts' average estimate of 36% and the 5-year average of 24%.

* In Russia, Sovecon agriculture consultancy lowered its 2026 wheat crop forecast to 88.9 million metric tons, down from 90.3 million tons, following a cut to its planted-area estimate.

* Ample rainfall and moderate temperatures across the U.S. Midwest continued to pressure corn and soybean prices, although traders warned that excessive moisture could begin to hamper crop development.

* Strong export demand lent some support to corn. The USDA confirmed private sales of 100,000 metric tons of corn to Mexico, including 30,000 tons for delivery in the 2025/26 marketing year and 70,000 tons for 2026/27 delivery.

* Commodity funds were net sellers of CBOT corn and soyoil futures, traders said on Tuesday. CBOT/FUNDS

MARKET NEWS

* Global stocks fell on Tuesday, dragged lower by a broad selloff in technology and semiconductor shares as investors continued taking profits on a long rally while bracing for more aggressive Federal Reserve action to fight inflation. MKTS/GLOB

DATA/EVENTS (GMT)

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0800 Germany Ifo Business Climate, Curr Conditions, Expectations New June

1400 US New Home Sales-Units May