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Concern about future of Ukrainian safe shipping channel
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Some east European states ban Ukrainian grain imports
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U.S corn planting weather in view
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Argentine soy exports slack
(Updates prices, adds quotes, changes headline, changes byline, changes dateline from previous HAMBURG)
MEXICO CITY, April 17 (Reuters) - Chicago wheat prices rose on Monday after Poland, Hungary and Slovakia banned grain and other food imports from Ukraine to protect their own agriculture sectors, casting further doubt on Ukrainian exports.
Corn was flat as cooler weather and some snow in the Midwest threatened to delay U.S. planting while soybeans rose on slow Argentine exports.
Chicago Board of Trade most-active wheat rose 0.55% to $6.86-1/4 a bushel at 10:28 CDT (1528 GMT). Corn gained 0.11% to $6.67 per bushel, soybeans rose 0.73% to $15.11-1/2 a bushel.
"Polish farmers are starting to protest about Ukraine grain and ag products depressing their prices, so that's a bit of a risk off," said Don Roose, president of U.S. Commodities.
Poland and Hungary announced bans on some imports from Ukraine on Saturday. Slovakia said on Monday it would do the same while other countries in central and eastern Europe were also considering action.
In response to individual country bans, the European Union's executive has said such unilateral action was unacceptable.
Kyiv aims to re-open food and grain transit via Poland as "a first step" to ending import bans at talks that began in Warsaw on Monday as countries halted grain from Ukraine to protect their local agriculture markets.
Additionally on Monday, Ukraine said the Black Sea grain deal was in danger of a "shutdown" after Russia blocked inspections of participating ships in Turkish waters.
Argentine soybean exports remain low after a poor crop, and grains inspectors launched a 24-hour strike that is halting shipments at key river ports in farm transport hub Rosario.
"Soybean (prices) found some strength from tightening supplies and the belief that ending stocks could come down in future reports," Roose said.
(Reporting by Cassandra Garrison in Mexico City, Michael Hogan in Hamburg, additional reporting by Naveen Thukral in Singapore; editing by Uttaresh Venkateshwaran, Janane Venkatraman and Krishna Chandra Eluri)
