PARIS/SINGAPORE: Chicago corn, wheat and soybean futures fell on Wednesday, giving up some gains from earlier this week after monthly US Department of Agriculture (USDA) forecasts failed to provide clear direction.

Traders were continuing to monitor weather in South America, where corn and soybean harvests are eagerly anticipated to help replenish declining US stocks, while also looking for further clues on Chinese demand and US spring planting.

The most-active wheat contract on the Chicago Board of Trade (CBOT) was down 1.5% at $6.46-3/4 a bushel by 1343 GMT, reversing a similar-sized gain from Tuesday.

CBOT soybeans were 1.5% at $14.18-3/4 a bushel, pulling away from a near seven-year high hit earlier this week.

Corn was 1.3% lower at $5.38-1/2 a bushel.

The USDA's March world crop report disappointed some market participants expecting the agency to trim US supply estimates. The USDA agency left unchanged its forecasts for US 2020/21 corn, soy and wheat ending stocks.

"This (March) report is typically a kick the can report. You've got so many things looming the next couple of months," Mike Lung of brokerage Allendale said in a market commentary.

Some traders are already looking ahead to end-March USDA estimates of US grain stocks and planting intentions for more clues about supply and demand.

The grain market is also wrestling with South American harvest prospects, with rain continuing to hamper soybean harvesting and corn planting in Brazil and dry conditions raising risks for yield loss in Argentina.

The USDA's world crop report provided some initial support for the wheat market by reducing its forecast of global stocks, notably due to increased feed demand in China.

But a bumper Australian harvest, rain forecast in dry US winter wheat belts and improving crop conditions in top exporter Russia were tempering supply concerns in wheat, trader said.