CHICAGO, March 9 (Reuters) - The U.S. Agriculture Department left its outlook for domestic corn and soybean supplies unchanged at seven-year lows on Tuesday.

USDA forecast in its monthly World Agricultural Supply and Demand Estimates report that the U.S. corn stocks will stand at 1.502 billion bushels by Aug. 31 and soybean stocks at 120 million bushels.

Analysts had predicted the report would show corn ending stocks of 1.471 billion bushels and soybean ending stocks of 117 million bushels, based on the average of estimates given in a Reuters poll. (Reporting by Mark Weinraub; Editing by Caroline Stauffer)