CHICAGO, April 11 (Reuters) - Soybean and corn production in Argentina will be smaller than previously thought as a crop wasting drought decimated fields in the key South American producer, the U.S. government said on Tuesday.

Argentina's soybean harvest was pegged at 27.00 million tonnes and the corn crop at 37.00 million tonnes, according to the U.S. Agriculture Department's monthly World Agricultural Supply and Demand Estimates report.

A month ago, USDA forecast Argentine soybean production at 33.00 million tonnes and corn production at 40.00 million tonnes. (Reporting by Mark Weinraub)