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Wheat up as Moscow says it could scrap Ukraine's grain deal

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Rain in U.S. wheat belts limits rise

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Corn down as U.S. planting weather reasonable

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Improved weather outlook for U.S. winter wheat curbs gains

HAMBURG, April 24 (Reuters) - Chicago wheat rose on Monday after Russia threatened to terminate a wartime grain deal allowing Ukrainian exports.

Corn dropped as U.S. planting weather remained positive, soybeans rose on buying interest after recent falls.

Chicago Board of Trade most-active wheat rose 0.2% to $6.74-3/4 a bushel by 1053 GMT. Corn fell 0.9% to $6.09-1/4 a bushel, soybeans rose 0.09% to $14.50-1/4 a bushel.

Former Russian president Dmitry Medvedev said if the G7 banned exports to Russia, Moscow would terminate the shipping deal enabling exports of grain from Ukraine.

“There is a feeling in the market that Ukraine’s shipping deal may not be extended, at least automatically, and there is not long to go before it expires in May,” said Matt Ammermann, StoneX commodity risk manager.

However, he said some form of compromise on Moscow's demands could not be ruled out with Russian foreign minister Sergei Lavrov scheduled to hold talks with the United Nations in New York on Monday.

“If the Ukrainian deal is not extended then other exporting countries would have to cover more demand.”

Rain forecast in U.S. wheat belts this week limited gains while corn fell on positive expectations for U.S. planting.

"U.S. corn planting progress in the next two weeks is likely to remain slowish, but there is still plenty of time to get the U.S. crop sown,” Ammermann said.

Soybeans saw bargain-buying after recent falls, against a bearish backdrop of a record Brazilian crop and the surge in exports, including more shipments to the United States, it is expected to lead to. (Reporting by Michael Hogan in Hamburg, additional reporting by Naveen Thukral in Singapore, editing by Sherry Jacob-Phillips and Kirsten Donovan)