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Wheat, corn firm with weather, Black Sea tensions in focus

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Markets await U.S. export sales data on Thursday

MEXICO CITY, April 12 (Reuters) - Chicago grains futures closed higher Wednesday, after a mixed day underpinned by renewed Russian criticism of the deal allowing Ukraine to export grain from Black Sea ports.

Soybean and corn futures also settled up, regaining some ground lost earlier in the session amid a bumper soy harvest in Brazil and an eye on weather conditions in the United States.

Wheat prices were getting support from the latest wrangling over the agreement.

Moscow, which agreed in mid-March to extend the arrangement for a reduced period until mid-May, said on Wednesday prospects for the deal were "not so great" as its own such exports still faced obstacles.

"That has been supportive to the wheat market here today, and a little bit for corn," said Jack Scoville, analyst with the Price Futures Group in Chicago.

East European Union countries near Ukraine have called for measures to curb flows of cheaper Ukrainian grain to their markets.

The most-active wheat contract on the Chicago Board of Trade (CBOT) settled up 5-1/2 cents at $6.79-1/2 per bushel.

Soybeans settled up 7 cents at $15.04-1/4 per bushel and corn closed 5 cents higher at $6.56 per bushel.

Markets were looking towards the U.S. Department of Agriculture weekly export sales report on Thursday.

Soybean production in Argentina will fall to a 23-year low and corn production to a five-year low due to drought, the U.S. Department of Agriculture (USDA) said on Tuesday as it cut sharply its forecasts for Argentina's crops.

But the USDA increased its outlook for Brazil's soy crop to a new record, while holding its projection for bigger corn output there this season.

(Reporting by Cassandra Garrison in Mexico City, Gus Trompiz in Paris and Naveen Thukral in Singapore; Editing by Subhranshu Sahu, Rashmi Aich, Sharon Singleton, Ed Osmond and Daniel Wallis)