"The war is going to have dramatic consequences for the world," said the EU's foreign affairs chief Josep Borrell.
Russia's blockade of Ukrainian grain exports is a "real war crime", the EU's top diplomat told reporters ahead of a meeting of foreign affairs ministers.
"It is inconceivable, one cannot imagine that millions of tonnes of wheat remain blocked in Ukraine while in the rest of the world people are suffering hunger," said Borrell, urging Russia to unblock the ports.
"This is a real war crime. So I cannot imagine that this will last much longer."
Borrell warned of the "risk of a great famine" in the world, but especially in Africa.
"It is the war which is creating price increases and scarcity on energy and food," Borrell said, emphasising that the EU's sanctions were not influencing the crisis as they don't target food or fertiliser.
He said the EU supported the United Nations' efforts to find a solution to unblock the exports, which have been held up since the beginning of Russia's invasion at the end of February.
"The problem comes from the Russian blockade of the Ukrainian grain. Millions of tonnes of wheat are being blocked."
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