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Corn futures drop on profit-taking, wheat falls for 2nd session

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U.S. corn harvest 20% complete, soy 22%; ratings steady - USDA

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Russia-Ukraine war to limit decline in Chicago wheat prices

SINGAPORE, Oct 4 (Reuters) - Chicago corn futures slid on Tuesday as traders took a breather after two straight sessions of gains, although the slower-than-expected pace of U.S. harvest provided a floor under the market.

Wheat declined for a second consecutive session, after climbing to a three-month high last week on the back of heightened Russia-Ukraine tensions.

The most-active corn contract on the Chicago Board of Trade (CBOT) lost 0.6% to $6.76-3/4 a bushel, as of 0329 GMT. Wheat lost 0.6% to $9.06-3/4 a bushel and soybeans gave up 0.1% to $13.72-1/4 a bushel.

The U.S. corn harvest was 20% complete as of Sunday, the U.S. Department of Agriculture (USDA) said in a weekly crop progress report on Monday, behind the average estimate in a Reuters analyst poll of 22% and the five-year average, also 22%.

The soybean harvest was farther ahead at 22% complete, surpassing the average analyst estimate of 20% but behind the five-year average of 25%.

Heightened tensions between Russia and Ukraine, the world's leading grain exporters, triggered worries over supplies.

Ukrainian forces have broken through Russia's defences in the south of the country while expanding their rapid offensive in the east, seizing back more territory in areas annexed by Moscow and threatening supply lines for Russian troops.

The escalation in Black Sea war came as the USDA said the 2022 U.S. wheat harvest was smaller than previously forecast and cut its crop assessment below analysts' expectations to 1.650 billion bushels.

In a separate quarterly stocks report, the USDA on Friday reported U.S. corn inventories were below analysts' expectations and soybean inventories topped estimates. The larger-than-expected soybean stocks added pressure to a soy market already under pressure from competition from South American supplies.

Commodity funds were net buyers of CBOT corn, soybean, soyoil and soymeal futures contracts on Monday and net sellers of wheat futures, traders said. (Reporting by Naveen Thukral; Editing by Subhranshu Sahu)