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Russia says Black Sea grain deal may be nearly over

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Parts of drought-hit Argentine soy fields to go unharvested

SINGAPORE, April 14 (Reuters) - Chicago wheat futures slid on Friday with ample world supplies weighing on prices, although losses were limited after Russia raised fresh doubts over the extension of a Black Sea deal to allow Ukrainian exports.

Soybeans were little changed amid concerns over a severe drought cutting output in top supplier Argentina.

"Currently, Russia is indicating that there will be no extension to the UN brokered Black Sea grain deal past May 18 unless the West removes a series of obstacles to the export of Russian grain and fertilizers," commodities research firm Hightower said in a report.

The most-active wheat contract on the Chicago Board of Trade (CBOT) lost 0.4% to $6.64-1/4 a bushel, as of 0236 GMT. Soybeans fell quarter of a cent to $15.00-3/4 a bushel while corn gave up 0.1% to $6.52-3/4 a bushel.

Wheat is set for a second week of losses, down 1.7%, soybeans and corn are up marginally this week.

Russia on Thursday said there would be no extension of the UN-brokered Black Sea grain deal beyond May 18 unless the West removed a series of obstacles to the export of Russian grain and fertiliser.

For soybeans, Argentina's Rosario grains exchange on Wednesday further cut its forecast for the 2022/2023 harvest to 23 million tonnes, down from the 27 million tonnes previously estimated, as a historic drought pummels the country's agricultural sector.

That came after the U.S. Department of Agriculture (USDA) on Tuesday cut its own forecast for the Argentine soybean crop to 27 million tonnes.

Argentina's Buenos Aires grains exchange on Thursday said farmers would likely leave large tracts of soy fields unharvested due to damage from a historic drought, which could lead to more cuts to its 25 million tonne production forecast.

The Rosario exchange also cut its forecast for Argentina's corn output to 32 million tonnes from 35 million previously.

China's March soybean imports rose 8% from the same month a year earlier, data showed on Thursday, bringing first quarter arrivals to a record even as demand failed to pick up as expected.

Brazilian farmers will produce a record 153.6 million tonnes of soybeans this season, an increase of 2.2 million tonnes compared to a March forecast as harvesting draws to a close in the world's biggest exporter of the oilseed.

In a report released Thursday by the government's food supply and statistics agency Conab, it cited adjustments in national average yield estimates as a factor for the upward revision.

A U.S. weather forecaster on Thursday predicted a 62% chance of the El Niño phenomenon developing in the Northern Hemisphere during May-July, and a strong chance toward end-year, likely compounding risks to crops across the globe.

Commodity funds were net sellers of CBOT corn, soybeans, wheat and soyoil futures contracts on Thursday, traders said. Funds were net buyers of soymeal futures, traders said. (Reporting by Naveen Thukral)