ROME, Aug. 7 -- Three consecutive months of rising food costs. That is what the United Nations food agency recorded in July, as wheat prices surged on Russian strikes targeting Ukrainian port infrastructure and heatwaves scorched harvests from the American Plains to southern Europe, pushing the global food price index to its highest level in nearly three years.

The UN Food and Agriculture Organization's food price index climbed to 131.1 points last month, a gain of 0.6 percent from June and the highest reading since January 2023. A 5.8 percent surge in wheat prices drove the advance, as fresh Russian strikes on the Odessa port corridor disrupted a critical export route and drought conditions cut into crops from Kansas to the Po Valley in...