PARIS/CANBERRA - Chicago wheat rose for a third day on Tuesday after the condition of U.S. crops worsened unexpectedly and stalemate ​in U.S.-Iran peace talks ⁠raised the risk of longer-lasting disruption to fuel and fertiliser supplies from the Gulf.

Corn and soybean futures ‌edged higher, underpinned by a jump in oil prices. Grain traders were also awaiting direction from Tuesday's U.S. government crop forecasts for ​next season and this week's U.S.-China summit, at which agricultural trade will be a focus.

The U.S. Department of Agriculture (USDA) on Monday ​rated 28% ​of the U.S. winter wheat crop in good-to-excellent condition, down from 31% a week earlier and the lowest for this time of year since 2022.

Analysts had on average expected the good/excellent rating ⁠to improve slightly to 32%. The figures reinforced doubts over whether recent showers have helped crops in drought-hit parts of the U.S. Plains. "The dry weather in U.S. growing regions is causing concern, which has pushed up the U.S. wheat price by more than 10% since the beginning of April," Commerzbank analysts said. The most traded wheat contract on ​the Chicago Board of ‌Trade (CBOT) was up ⁠1.5% at $6.43-1/2 a bushel ⁠by 1047 GMT. Kansas wheat futures, which represent the variety most affected by drought, were up 2% at $7.00 a bushel. Oil prices ​extended gains after U.S. President Donald Trump said the ceasefire with Iran was "on ‌life support". Grains have tended to track crude oil during the Iran war ⁠because corn and soyoil are widely used for biofuel. The conflict also threatens to weigh on farm production through higher fertiliser and energy costs. "We are not going to see any resolution in Hormuz for a while. Supply issues will last for longer, and potentially into the Northern Hemisphere winter seeding period," Rabobank analyst Vitor Pistoia said of the Strait of Hormuz trade route that has effectively been closed by Iran.

World wheat and corn production next season will fall back from record highs while soybean output will hit a new peak, U.S. consultancy AgResource said on Tuesday. CBOT corn was up 0.2% at $4.76 a bushel and soybeans added 0.3% ‌at $12.16-1/4. Grain traders are awaiting the USDA's first full global crop outlook for ⁠2026/27, due at 1600 GMT.

Chinese purchases of U.S. agricultural goods are a ​priority for U.S. President Donald Trump's May 14-15 summit with Chinese President Xi Jinping, though traders and analysts said any deal could be limited by Beijing's unwillingness to go beyond a soybean purchase commitment made last October. Prices at 1047 ​GMT Last Change Pct Move CBOT wheat 643.50 9.50 1.50 CBOT ‌corn 476.00 0.75 0.16 CBOT soy 1216.25 3.25 0.27 Paris wheat 210.75 2.50 1.20 Paris maize 213.50 0.75 0.35 Paris rapeseed 519.50 4.50 0.87 WTI crude oil 101.34 3.27 3.33 Euro/dollar 1.17 0.00 -0.31 Most active contracts - Wheat, corn and soy U.S. cents/bushel, ⁠Paris futures in euros per metric ton