(NewsNation) — Russia’s invasion of Ukraine is heightening a global food crisis, causing a growing list of key producing countries seeking to keep vital food supplies within their borders and prompting food price hikes.

Ukraine’s government Wednesday banned the export of wheat, oats and other staples that are crucial for global food supplies as authorities try to ensure they can feed people during Russia’s intensifying war.

Russia and Ukraine together supply nearly a third of the world’s wheat and barley exports, which have soared in price since the invasion.

Russia was the world’s largest exporter of wheat in 2019, according to data gathered by the Observatory of Economic Complexity. Ukraine was also top producer coming in at number five.

An economic adviser to Ukraine’s president predicted this crisis could cause a 10 to 50% drop of the global supply of major products like wheat, corn and sunflower oil.

New rules on agricultural exports introduced this week also prohibit the export of millet, buckwheat, sugar, live cattle, and meat and other “byproducts” from cattle, according to a government announcement.

The export ban is needed to prevent a “humanitarian crisis in Ukraine,” stabilize the market and “meet the needs of the population in critical food products,” Roman Leshchenko, Ukraine’s minister of agrarian and food policy, said in a statement posted on the government website and his Facebook page.

It’s the latest sign that Russia’s invasion of Ukraine threatens the food supply and livelihoods of people in Europe, Africa and Asia who rely on the farmlands of the Black Sea region — known as the “breadbasket of the world.”

Ukraine is also the world’s largest exporter of both grain and vegetable oil.

This has major impacts in the United States, because higher prices for basic grains will cause food manufacturers to raise prices and pass those costs along to consumers.

The export ban will likely reduce global food supplies just when prices are at their highest level since 2011.