GRAINS-Wheat gains on crop risks, soybeans firm on export sales

* Wheat hits 3-week high as U.S. wheat faces cold after drought

* Soybeans up over 1 pct, export sales ease trade war fears

* Corn edges higher, investors eye biofuel policy indications

(Updates with European trading, changes byline/dateline) PARIS/SYDNEY, April 9 (Reuters) - Chicago wheat futures rose on Monday to a three-week high as cold weather threatened to stress U.S. wheat already weakened over a U.S.-Chinese trade dispute. Corn was marginally higher. The U.S. government last Monday gave its lowest rating for winter wheat for the time of year since 2002, following drought in the U.S. Plains, and some crops have since endured a cold spell. "There are concerns about cold temperatures causing some frost damage, coming after last week's U.S. Department of Agriculture crop report that showed the damage of recent dry weather," National Australia Bank agribusiness economist Phin Ziebell said. Freezing conditions since late last week could also delay planting of the country's spring crop, which the government has expected to gain extra acreage this year. The weather represented "heightened risks to U.S. winter wheat yield and spring wheat planting," Thomson Reuters Agriculture Research analysts said, adding that little moisture was expected for crops up to mid-April. The most active wheat futures on the Chicago Board Of Trade were up 1.1 percent at $4.77-1/2 a bushel by 1050 GMT. The contract earlier rose as high as $4.81-3/4, a level last reached on March 16, adding to its 1.6 percent gain from Friday. The most active CBOT soybean futures were up 1.2 percent at $10.46 a bushel, while the most active corn contract inched 0.3 percent higher to $3.89-1/2 a bushel. Escalating tensions between the United States and China have triggered U.S. soybean purchases by European buyers, after Chinese demand sent Brazilian prices surging. Investors took heart from comments by U.S. government officials playing down the threat of a trade war with China, despite tit-for-tat tariff proposals in the past week. The inclusion of soybeans by China, the world's biggest importer of the oilseed, on a list of U.S. goods that could be subject to retaliatory duties, sent soybean futures plunging last Wednesday. Corn prices were more subdued, with traders awaiting news on President Donald Trump's policy on biofuel, a major outlet for U.S. corn. Grain markets were also looking ahead to Tuesday's monthly supply and demand forecasts from the U.S. Department of Agriculture (USDA) that could bring revisions to projected South American corn and soybean output, along with adjustments to the U.S. balance sheet.

Prices at 1050 GMT

Last Change Pct End Ytd Pct Move 2017 Move CBOT wheat 477.50 5.25 1.11 427.00 11.83 CBOT corn 389.50 1.00 0.26 350.75 11.05 CBOT soy 1046.00 12.25 1.19 961.75 8.76 Paris wheat May 167.75 0.75 0.45 162.50 3.23 Paris maize Jun 168.00 0.50 0.30 163.50 2.75 Paris rape May 353.25 0.75 0.21 352.75 0.14 WTI crude oil 62.24 0.18 0.29 60.42 3.01 Euro/dlr 1.23 0.00 -0.11

Most active contracts - Wheat, corn and soy US cents/bushel, Paris futures in euros per tonne

(Reporting by Gus Trompiz in Paris and Colin Packham in Sydney; Editing by Biju Dwarakanath)