Changes advisory to wheat price weakness

HAMBURG, May 29 (Reuters) - Chicago wheat and corn futures fell on Friday and soybeans rose as the market assessed the impact of a possible new ceasefire deal between the United States and Iran.

Crop-friendly weather in U.S. grain belts was also in focus.

Crude oil futures, a major influence on grains recently, fell after reports that the U.S. and Iran had reached agreement on a potential ceasefire extension. Markets expect any U.S.-Iran peace deal will cause sharp commodity price falls.

Chicago Board of Trade most-traded wheat Wv1 fell 0.1% to $6.23-1/4 a bushel at 1055 GMT. Corn Cv1 fell 0.3% to $4.54-1/4 a bushel, soybeans Sv1 rose 0.3% to $11.99 a bushel.

"Wheat, corn and soybeans are mixed today as the market assesses what a possible U.S./Iran 60 day ceasefire means exactly, as technically there has been a ceasefire since April," said Matt Ammermann, commodity risk manager at StoneX. "U.S. Midwest weather continues to be beneficial with some needed heat, weakening wheat but soon the need for rains will be there as well for the U.S. corn and soybean crops."

Expectations of strong demand for soyoil for biofuel blending in U.S. fuels under the renewable volume obligations (RVOs) were also supportive for soybeans.

"Soybeans continue to lean a bit higher, still the bean oil narrative remains supportive for the complex as U.S. bean oil cash supplies remain in high demand amid RVO obligations and record crush margins right now," Ammermann said.

Wheat gains were limited by upcoming Northern Hemisphere harvests. While the U.S. crop has suffered from drought, many other countries are on track for good crops.

China could start buying U.S. soybeans and farm products under the new trade deal, traders said.

Russia is expecting a decent 2026 grain harvest, the country's Agriculture Minister said on Friday, signalling export competition to the U.S. and other suppliers