Corn around 3-week low on selling pressure, easing supply concern

* Corn futures fall for 4th session

* Near lowest since late April

* Wheat prices see spillover weakness from corn (Adds continued weakness in European trade, comment)

SINGAPORE/HAMBURG, May 17 (Reuters) - Chicago corn prices fell for a fourth straight session on Monday, dropping to the lowest in almost three weeks on selling pressure and easing concerns over supplies.

Wheat saw spillover weakness from corn, while soybean prices also dropped. Corn had hit eight-year highs last week on fears of tight world supplies.

"The agriculture market got a bit ahead of itself," said Phin Ziebell, agribusiness economist at the National Australia Bank. "We are seeing liquidation of long positions which was triggered by U.S. forecast of higher than expected supplies.”

Chicago Board of Trade most-active corn fell 0.5% to $6.40-1/2 a bushel at 0944 GMT, after hitting its lowest since April 28 at $6.33 a bushel earlier on Monday.

Wheat fell 1.8% to $6.94-1/2 a bushel, soybeans fell 0.1% to $15.84 a bushel.

Large speculators cut their net long position in CBOT corn futures in the week ended May 11, data on Friday showed.

Funds staged the biggest corn sell-off since 2019, ahead of a U.S. Department of Agriculture (USDA) report last week, Reuters analyst Karen Braun said.

The U.S. Department of Agriculture (USDA) last week forecast 2021/22 season U.S. corn stocks above most analysts' expectations.

"The price slide was sparked by last Wednesday’s forecasts from the U.S. Department of Agriculture," Commerzbank said in a note. "It painted a less tight situation on the grains markets in the 2021/22 season than most observers had been expecting. Ever since, prices have been tumbling across the board."

Analytics firm IHS Markit Agribusiness forecast U.S. 2021 corn plantings at 96.8 million acres, up from the USDA's forecast of 91.1 million acres.

"Oilseed prices have been faring better than grains prices in recent days which is hardly surprising given that the USDA expects the situation to remain tight on the soybean market," Commerzbank added. (Reporting by Michael Hogan and Naveen Thukral, editing by Emelia Sithole-Matarise)