GRAINS-Corn, soybean ease ahead of USDA report, wheat flat

* Wheat slips on pressure from U.S. winter wheat harvest

* Rains in Australia seen improving wheat crop condition

* U.S. corn, soybean crops benefit from wet weather

(Updates prices, adds comments) SINGAPORE/PARIS, June 28 (Reuters) - Chicago corn and soybeans futures lost ground on Thursday ahead of a key U.S. government report due on Friday expected to raise estimates of U.S. 2018 corn and soybean plantings. Wheat was trading sideways given ample global supplies and pressure from harvest of the U.S. winter crop that weighed on the market. The most-active soybeans contract on the Chicago Board Of Trade slipped 0.3 percent to $8.86-1/4 a bushel as of 1149 GMT and corn also dipped 0.3 percent to $3.72 a bushel. Wheat was unchanged at $4.88-1/2 a bushel, having closed 1.1 percent higher on Wednesday. Agricultural markets are bracing for the U.S. Department of Agriculture's acreage and quarterly stocks reports on Friday. "The USDA's report is coming up and it is expected to raise production estimate(s) on corn, beans given the ideal weather in much of the U.S. Midwest," said Phin Ziebell, agribusiness economist, National Australia Bank. Analysts surveyed by Reuters on average expect the USDA to raise the estimate of U.S. 2018 corn and soybean plantings from its March forecast, and to report multi-year highs in U.S. June 1 corn and soy stockpiles. "Corn and soybean prices are under pressure ahead of tomorrow's figures for U.S. stocks and planted acreage," Commerzbank said in a note. "Looking at the average estimates, June stocks of corn are likely to be the highest since 1988, while June stocks of soybeans are even expected to set a new record." Soybean prices could find some support on hopes that U.S.-China trade tensions would abate soon. U.S. President Donald Trump said on Wednesday he will use a strengthened national security review process to thwart Chinese acquisitions of sensitive American technologies - a softer approach than imposing China-specific investment restrictions.

Wheat is facing pressure from the continuing U.S. winter wheat harvest and falling prices in Russia. The U.S. Department of Agriculture said late on Monday the U.S. winter wheat harvest was 41 percent complete, while the Kansas harvest was 52 percent finished, ahead of the state's five-year average of 32 percent. Australia's drought-hit, grain-producing areas are expected to get some rains. In Ukraine's southern and central regions, farmers have harvested around 2.7 million tonnes of grain from the 2018 harvest and the yield averaged 3.06 tonnes per hectare, the agriculture ministry said on Wednesday.

Prices at 1149 GMT

Last Change Pct End Ytd Move 2017 Pct

Move

CBOT wheat July 488.50 0.00 0.00 427.00 14.40 CBOT corn July 372.00 -1.25 -0.33 350.75 6.06 CBOT soy July 886.25 -2.75 -0.31 951.75 -6.88 Paris wheat May 179.00 0.75 0.42 162.50 10.15 Paris maize Jun 163.75 0.00 0.00 163.50 0.15 Paris rape May 356.75 0.00 0.00 347.75 2.59 WTI crude oil 72.59 -0.17 -0.23 60.42 20.14 Euro/dlr 1.16 0.00 0.23

Most active contracts - Wheat, corn and soy US cents/bushel, Paris futures in euros per tonne

(Reporting by Naveen Thukral, Editing by Sherry Jacob-Phillips/Mark Heinrich)