(Updates prices, adds quotes; changes byline, dateline, previous LONDON) CHICAGO, April 11 (Reuters) - U.S. wheat futures fell roughly 1 percent on Wednesday amid reminders of plentiful global supplies and some outlooks for rain in the Plains wheat belt late next week. Corn declined on technical selling and soybeans turned lower, a day after the spot May contract set a one-month top. Chicago Board of Trade May soft red winter wheat settled down 4-3/4 cents at $4.87-1/4 per bushel. May corn ended down 2-1/4 cents at $3.87 and May soybeans fell 2-1/4 cents at $10.47-3/4 a bushel. Wheat slipped as traders digested Tuesday's monthly U.S. Department of Agriculture (USDA) supply/demand report in which the government raised its forecast of world 2017-18 wheat ending stocks to a record-high 271.2 million tonnes. "Wheat prices are ... under modest pressure today after (Tuesday's) USDA report confirmed old-crop supplies exceeding a nine-month supply for soft red winter and an eight-month supply for hard red winter wheat," INTL FCStone chief commodities economist Arlan Suderman said in a note to clients. Additional pressure stemmed from a sharp decline in Russia's currency that could diminish wheat export prospects in the United States and European Union. "This is providing a further factor of competitiveness for the Russian wheat on international markets. We consider that Russia could export 40 million tonnes in this marketing year," Agritel said in a market note. Some forecasts also called for a better chance of rain late next week in the drought-hit southern Plains. "The forecast now shows rainfall developing across much of the hard red winter wheat belt by next Friday. Confidence is still quite low, however," Radiant Solutions said in a daily weather note. Spring wheat futures climbed on the Minneapolis Grain Exchange, bucking the weaker trend as outlooks for wintry weather in the northern Plains threatened to delay planting in that region. CBOT corn fell in technically driven trade amid a lack of fresh supportive news. The USDA on Tuesday raised its forecast of U.S. 2017-18 corn ending stocks to 2.182 billion bushels, roughly in line with trade expectations. Soybean futures turned lower in the last half hour of trade as traders booked profits a day after the spot May contract touched a one-month high of $10.64 a bushel. Soybeans drew early support from fresh export demand. Argentina purchased an additional 120,000 tonnes of soybeans from the United States after buying the same volume on Tuesday. The purchases mark Argentina's largest soybean imports from the United States in 20 years, showing the impact of a prolonged drought on the South American country, which is the world's No. 3 exporter of raw soybeans.
CBOT settlement prices:
Last Net Pct Volume
CBOT wheat WK8 487.25 -4.75 -1.0 95548 CBOT corn CK8 387.00 -2.25 -0.6 134577 CBOT soybeans SK8 1047.75 -2.25 -0.2 108046 CBOT soymeal SMK8 380.20 -3.70 -1.0 68931 CBOT soyoil BOK8 31.53 -0.32 -1.0 86124
NOTE: CBOT May wheat, corn and soybeans shown in cents per bushel, soymeal in dollars per short ton and soyoil in cents per lb.
(Additional reporting by Nigel Hunt in London and Colin Packham in Sydney; editing by Mark Potter and G Crosse)