CBOT December corn settled down 1 cent at $3.74-1/4 per bushel but held above support at its 100-day moving average near $3.72.

The US Energy Information Administration said weekly US output of corn-based ethanol fell to 1.01 million barrels per day, the lowest since April, while stocks of the biofuel rose to 24.13 million barrels, the most since March.

The Environmental Protection Agency aims to release its draft rule allowing year-round sales of higher ethanol gasoline blends by February, and end deliberations on the proposal by May, according to a filing with the Office of Management and Budget.

Ahead of the US Department of Agriculture's weekly export sales report on Thursday, analysts expected the government to show weekly corn sales at 800,000 to 1.3 million tonnes.

Mostly dry weather expected in the US Midwest over the next 10 days should bolster harvest progress, the Commodity Weather Group said in a client note.