The prices of oil, gasoline, fertilizer and agricultural products shot up earlier this year when Western nations imposed sanctions on Russia after its invasion of Ukraine.

Wheat and sunflower oil costs were also hit hard because Ukraine is a major exporter. Oil prices have begun to drop back this week to pre-invasion levels as traders brace for a sharp drop-off in demand, but food price inflation remains high.

See: How to save up to 50% on your grocery bill and reduce food waste

U.S. consumer price index figures for June show that the price of chicken and flour are each up close to 20% from a year earlier and margarine has jumped 34%.

“We talk a lot about gasoline prices because that’s what affects Americans, but the bigger issue is food,” Fink said.

See: Avoid these food items the next time you go shopping if you want to drastically cut your grocery bill

“There has been tremendous destruction of arable land in Ukraine. … Globally the cost of fertiliser is up almost 100 per cent and that additional cost is reducing the amount of fertiliser used in farming. That is harming the quality of the crop worldwide,” he said.

Although lower crude-oil prices have started to feed through to the price at the pump for motorists, consumer-goods companies are continuing to see high input costs. Any drop in fertilizer prices is likely to come too late to boost this year’s food harvests.

The World Bank forecast after the invasion that global food prices would rise 20% this year, far outpacing raw materials.

The impact is particularly grim in Africa, which usually imports grain from Ukraine as well as producing its own food. Fertilizer prices there have risen 300%, and the continent is facing a shortage of 2 million metric tons, according to the African Development Bank.

Janet Yellen, the U.S. Treasury secretary, said on Friday that the world was facing “an extremely difficult time for global food security” and urged the G-20 leading nations to halt stockpiling and export restrictions on food and provide additional financial assistance to countries and people struggling with food insecurity.

See: G20 finance ministers work on tackling inflation and food shortages

Bill Gates, the philanthropist and Microsoft co-founder, flagged similar concerns this week, saying that the reduction in supplies of wheat, edible oils and other foods caused by the war in Ukraine was “driving up food prices, which will increase malnutrition and instability in low-income countries.”

He noted in a blog post that improving agricultural productivity in Africa required “far more investment.”

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