(Updates U.S. market activity to close)
By Michael Hirtzer
CHICAGO, Nov 7 (Reuters) - U.S. soybean futures rose for the third straight session on Monday, boosted by robust export demand, while wheat and corn futures eased due to caution ahead of Tuesday's U.S. elections and a key supply-demand report.
Chicago Board of Trade soybean and soymeal prices each gained nearly 1 percent after the U.S. Department of Agriculture said exporters sold 132,000 tonnes of U.S. soybeans to China and 135,000 tonnes of U.S. soymeal to the Philippines. Exporters also sold 172,000 tonnes of U.S. corn to unknown destinations, USDA said.
"Exports for soy have been on fire. That's the supporting factor for soybeans," said Dax Wedemeyer, broker at U.S. Commodities Inc.
CBOT January soybean futures finished 7-3/4 cents, or 0.8 percent, higher at $9.98-1/2 per bushel.
CBOT December wheat fell 4-1/4 cents to $4.10 per bushel and CBOT December corn eased 2-1/2 cents to $3.46-1/4, with each grain trimming losses late in the session.
Gains in the dollar against a basket of currencies made U.S. goods comparatively more expensive in global markets and weighed on wheat and corn prices. Wheat has been struggling to compete in export markets due to cheaper supplies and freight costs on offer out of Russia and eastern Europe.
The buying agency for top importer Egypt after the close of trading said it was seeking wheat for Dec. 10-20 shipment.
With the harvest of record-large U.S. soybean and corn crops nearly complete, many investors were waiting to see if demand would help draw down the big supplies.
Kaname Gokon at brokerage Okato Shoji in Tokyo said the market was focused on the U.S. elections and Wednesday's USDA monthly supply and demand report.
"But there is no change in fundamentals; there is aggressive export demand for U.S. soybeans and cash market is a bit tight. In Argentina, farmers are likely to plant more corn and less soybeans which is supportive for prices."
Analysts polled by Reuters expected the USDA on Wednesday to raise its forecast for U.S. soybean production to a record high and slightly reduce its outlook for U.S. corn output. Analysts also predicted the agency would narrowly increase U.S. wheat ending stocks. (Additional reporting by Sybille de La Hamaide in Paris and Naveen Thukral in Singapore; Editing by James Dalgleish and Meredith Mazzilli)