Russian missiles bombarded the major port of Odesa in southern Ukraine today just hours after a deal was signed to unblock grain exports from the Black Sea.
The agreement signed by Moscow and Kyiv on Friday is crucial to curbing soaring global food prices.
It will allow certain exports to be shipped from Black Sea ports including Odesa.
United Nations officials had said they hoped the agreement would be operational in a few weeks but it is not clear if that will be possible after today’s strikes.
Two missiles hit the port while another two were shot down by air defence forces, said Ukrainian military commanders.
The US ambassador to Kyiv, Bridget Brink, called the strike outrageous.
She said: “The Kremlin continues to weaponise food. Russia must be held to account.”
The United States is exploring whether it can send fighter jets to Ukraine, a White House spokesman said.
The blockade of Ukrainian ports by Russia’s Black Sea fleet since Moscow’s February 24 invasion has trapped tens of millions of tons of grain.
Russia and Ukraine are major global wheat suppliers, and the war sent food prices soaring.
A global food crisis has pushed 47 million people into acute hunger. Meanwhile heartbreaking pictures of five women fighters who died in the siege of Mariupol in May were released.
They were among 100 people killed by two Russian missiles on their bunker in the Azovstal steelworks.
Alla Taran, 33, died alongside her husband Vitaliy, leaving their son, three, orphaned.
Anastasia Kunytska, 23, was also killed along with her three unnamed comrades.
Her sister Olga, 17, said: “These women courageously held the line against the Russian onslaught.”