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U.S. winter wheat ratings lowest on record; corn 8% planted

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Ukraine grain import bans mount as Kyiv seeks transit deal

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US March soybean crush at 185.810 mln bushels, 2nd highest ever

SINGAPORE, April 18 (Reuters) - Chicago wheat rose above $7 a bushel for the first time in nearly three weeks on Tuesday after a U.S. government report showed the condition of winter crop at an all-time low, and several Eastern European countries banned grain imports from Ukraine, raising global supply concerns.

Soybeans edged higher on support from strong U.S. processing data, while corn firmed on slow pace of U.S. planting.

"The USDA's latest weekly crop progress report for the U.S. shows that the winter wheat crop condition remains poor due to extended drought conditions in major producing regions," ING said in a note.

The most-active wheat contract on the Chicago Board of Trade (CBOT) gained 0.9% at $7.13-1/2 a bushel, as of 0238 GMT, after climbing earlier in the session to its highest since March 29 at $7.14-1/4 a bushel.

Soybeans rose 0.6% to $14.93-3/4 a bushel and corn added 0.3% to $6.44-1/4 a bushel.

The U.S. Department of Agriculture (USDA) on Monday rated 27% of U.S. winter wheat in good to excellent condition, unchanged from a week ago and the lowest for this time of year in records dating to the late 1980s.

For corn, the USDA said planting was 8% complete by Sunday, behind the average analyst estimate of 10% but ahead of the five-year average of 5% as farmers took advantage of mild weather.

Global wheat supplies are being threatened, with several countries in Europe banning imports from war-torn Ukraine.

Slovakia on Monday joined Poland and Hungary in banning grain imports from Ukraine as even Kyiv's staunchest allies come under domestic pressure to shield their agriculture markets.

In addition, Ukraine said the Black Sea grain deal was in danger of a "shutdown" after Russia blocked inspections of participating ships in Turkish waters.

In the soybean market, the U.S. crush jumped to a 15-month high and the second highest level for any month on record in March, according to National Oilseed Processors Association (NOPA) data released on Monday.

NOPA members, which account for around 95% of soybeans crushed in the United States, processed 185.810 million bushels of soybeans last month, up 12.3% from the 165.414 million bushels processed in February.

Argentina grains inspectors have launched a 24-hour strike that is halting shipments at key river ports in farm transport hub Rosario, the ports chamber CAPyM said on Monday.

Commodity funds were net buyers of CBOT grains and soy futures contracts on Monday, traders said. (Reporting by Naveen Thukral; Editing by Subhranshu Sahu and Uttaresh Venkateshwaran)