(Recasts throughout; updates prices, adds quotes; changes byline, dateline, previous PARIS/SINGAPORE) CHICAGO, Oct 20 (Reuters) - U.S. corn and soybean futures fell to their lowest levels in a week on Friday, pressured by active harvest progress in the heart of the Midwest crop belt, analysts said. The exception to the weak trend was soyoil futures, which hit their highest in nearly a month on news the U.S. Environmental Protection Agency was backing down on reforms to the nation's renewable fuel program. As of 12:23 p.m. CDT (1723 GMT), Chicago Board of Trade December corn was down 4 cents at $3.45 per bushel, its weakest since the Oct. 12 contract low of $3.42-1/2. CBOT November soybeans were down 5 cents at $9.81-1/2 a bushel while December soyoil was up 0.32 cent at 34.15 cents per pound. CBOT December wheat was down 3-1/2 cents at $4.29-1/4 a bushel. Corn posted the biggest decline on a percentage basis, pressured by this week's optimal weather for combines rolling in the Midwest. However, showers were expected to slow fieldwork in some areas this weekend. "It's been a good harvest week. Everyone is going like crazy until the rain starts," said Brian Hoops, analyst with Midwest Market Solutions. "The export business we had yesterday and this morning was certainly a supportive feature, but not enough to sustain an up-trending market when you have harvest going on," Hoops said. The U.S. Department of Agriculture said private exporters in the last day sold a total of 245,000 tonnes of U.S. corn to Spain and unknown destinations, along with 198,000 tonnes of soybeans to China. The USDA had announced another 384,000 tonnes of soybeans sold to China a day earlier. CBOT soyoil futures climbed for a second straight session on expectations of demand for soy-based biodiesel fuel. The December contract pushed through its 50-day moving average and reached 34.47 cents a pound, its highest since Sept. 22, before paring gains. The soyoil rally followed news that the EPA will keep volume mandates for renewable fuel - including corn-based ethanol and soy-based biodiesel - for next year at or above proposed levels, reversing a previous move to open the door to cuts. CBOT wheat drifted lower in featureless trade, following a light bounce a day earlier tied to better-than-expected U.S. export sales data. Rallies in wheat have been curbed by the prospect of record global inventories this season, supported by a record Russian crop. Consultancy SovEcon Thursday upgraded its forecast for Russia's 2017/18 wheat exports to 33.9 million tonnes from 32.4 million previously.
CBOT prices as of 12:23 p.m. CDT (1723 GMT):
Last Net Pct Volume
CBOT wheat Wc1 429.00 -3.75 -0.9 28799 CBOT corn Cc1 345.00 -4.00 -1.2 140140 CBOT soybeans Sc1 981.50 -5.00 -0.5 122326 CBOT soymeal SMc1 318.10 -3.30 -1.0 46472 CBOT soyoil BOc1 34.16 0.33 1.0 55964
NOTE: CBOT December wheat, December corn and November soybeans shown in cents per bushel, December soymeal in dollars per short ton and December soyoil in cents per lb.
(Additional reporting by Naveen Thukral in Singapore and Gus Trompiz in Paris; Editing by Mark Heinrich and Cynthia Osterman)