CHICAGO: Spot basis bids for soybeans firmed at US Midwest river elevators early on Monday, with a recent spate of export sales boosting the need for supplies to be shipped by barge to export terminals.

The corn basis was steady to weak at river elevators.

Around the interior, the corn basis was firm at processors and steady at elevators.

Soybean bids were flat at interior elevators and steady to weak at processors, falling by 10 cents per bushel in Lincoln, Nebraska.

Soybean processors have faced tightening soy margins in recent weeks, cutting their demand for crush supplies.

Corn bids were mixed at ethanol plants.

Farmer sales were slow on Monday morning, an Iowa dealer said.