Wheat futures extended a sharp rally as Chicago prices touched a three-year high and Euronext benchmarks reached a one-month peak, with traders bracing for further escalation in the Russia-Ukraine war that has brought Black Sea grain shipments near a standstill. The Euronext December contract rose 0.6% to 246.75 euros per metric ton after touching 249 euros, its highest since July 24. Chicago wheat climbed as much as 2.6%, building on a prior 6.4% jump that included a limit-up move, and has gained roughly 19% this month. Market sentiment shifted after reports that Russia is preparing to intensify attacks on Ukraine, including infrastructure, after concluding peace talks have stalled. Ukraine faces a drop of more than half in agricultural exports this season versus earlier estimates, while Russian wheat shipments are expected to fall more than 50% in August year on year. Russia and Ukraine together account for more than a quarter of global wheat exports, forcing importers to seek costlier alternatives and raising food inflation risks.