The ship Navi-Star, seen July 29, sits full of grain since Russia’s invasion of Ukraine began five months ago as it waits to sail from the Odesa Sea Port in Ukraine. David Goldman,/Associated Press

KYIV, Ukraine — Russia resumed its blockade of Ukrainian ports on Sunday, cutting off urgently needed grain exports to hungry parts of the world in what U.S. President Biden called a “really outrageous” act.

Biden warned that global hunger could increase because of Russia’s suspension of a U.N.-brokered deal to allow safe passage of ships carrying grain from Ukraine, one of the world’s breadbaskets.

“It’s really outrageous,” Biden said Saturday in Wilmington, Delaware. “There’s no merit to what they’re doing. The U.N. negotiated that deal and that should be the end of it.”

Biden spoke hours after Russia announced it would immediately halt participation in the grain deal, alleging that Ukraine staged a drone attack Saturday against Russia’s Black Sea Fleet off the coast of occupied Crimea. Ukraine has denied the attack, saying that Russia mishandled its own weapons.

Ukraine’s Infrastructure Ministry reported Sunday that 218 ships involved in grain exports have been blocked – 22 loaded and stuck at ports, 95 loaded and departed from ports, and 101 awaiting inspections.

One of the blocked ships, carrying 40,000 tons of grain bound for Ethiopia under a U.N. aid program, could not leave Ukraine on Sunday as a result of Russia’s “blockage of the grain corridor,” Oleksandr Kubrakov, Ukraine’s minister of infrastructure, said on Twitter. He didn’t specify which Ukrainian port the ship, the Ikraia Angel, was stuck in.

The grain initiative – an example of rare wartime cooperation between Ukraine and Russia – has allowed more than 9 million tons of grain in 397 ships to safely leave Ukrainian ports since it was signed in July. U.N. chief António Guterres had urged Russia and Ukraine on Friday to renew the deal when it expires Nov. 19. The grain agreement has brought down global food prices about 15% from their peak in March, according to the U.N.

A Ukrainian soldier inspects a Russian tank that was damaged in recent fighting Sunday near the recently retaken village of Kamianka, Kharkiv region, Ukraine. Efrem Lukatsky/Associated Press

Ukrainian President Volodymyr Zelenskky expressed outrage at Russia’s decision.

“Why is it that a handful of people somewhere in the Kremlin can decide whether there will be food on the tables of people in Egypt or Bangladesh?” he said Saturday in his nightly video address.

Two initiatives to revive the grain deal were reported Sunday.

Turkish Defense Minister Hulusi Akar was in talks with his counterparts to “solve the problem and to continue the grain initiative,” his agency said, adding that no more grain ships would leave Ukraine but those already waiting near Istanbul would be inspected on Sunday or Monday.

At the United Nations in New York, Guterres delayed a trip by a day to engage in talks aimed at ending Russia’s suspension of the grain export deal. Russia also requested a meeting Monday of the U.N. Security Council to discuss the topic.

Analysts say Russia’s withdrawal shows that it sees the grain deal as yet another way to pressure Ukraine.

“By leaving the deal now and putting the blame on Ukraine, it aims to slow Ukrainian attacks around the Black Sea,” said Mario Bikarski, a Economist Intelligence Unit analyst. Russia could be hoping that Ukraine’s Western allies might ask it to focus its forces elsewhere to save the grain deal, he said.

More conflicting details emerged Sunday about the alleged attack on Russia’s Black Sea Fleet.

The city council of Mariupol, a Ukrainian port now controlled by Russia, claimed on Telegram that Ukrainian special services had destroyed at least three Russian warships near the city of Sevastopol on the Russian-annexed Crimean Peninsula.

But an adviser to Ukraine’s Interior Ministry claimed that the Russians’ “careless handling of explosives” had caused blasts on four Russian warships. Anton Gerashchenko wrote on Telegram that the vessels included a frigate, a landing ship and a ship that carried cruise missiles.

Reports have surfaced for months of Ukrainian sabotage of Russian warplanes and ammunition depots on Crimea and Zelenskky has vowed repeatedly to recapture the strategic Black Sea peninsula that Russia annexed in 2014.

A woman gets bread and other aid from a volunteer in Bakhmut, the site of the heaviest battle against the Russian troops in the Donetsk region, Ukraine, on Friday. Efrem Lukatsky/Associated Press

Russia’s Defense Ministry claimed Sunday that one Ukrainian drone that reportedly attacked Sevastopol appeared to emanate from a civilian ship carrying agricultural products from Ukraine. The ministry claimed an inspection of the wreckage showed the drones used Canadian-made navigation and their the launch point was the Ukrainian coast near the port of Odesa.

Independent verification of each side’s claims was not possible.

Ukraine appears to have targeted the Black Sea Fleet and other Russian military infrastructure on Crimea – far from the front lines but a critical launching pad for attacks against Ukraine – since the spring, although it often doesn’t confirm its responsibility.

On the battlefront, Russian missile attacks kept pounding key front-line hot spots in Ukraine. The Russians shelled seven Ukrainian regions over the past 24 hours, killing at least five civilians and wounding nine more, Ukraine’s presidential office said.

In the eastern Donetsk region, where the fighting is ongoing near the cities of Bakhmut and Avdiivka, eight cities and villages were shelled.

Earlier this month, Moscow intensified its missile and drone strikes on Ukraine’s power stations, waterworks and other key infrastructure, damaging 40% of Ukraine’s electric system and forcing the government to implement rolling blackouts. Kyiv’s mayor said the Ukrainian capital’s power system was operating in “emergency mode.”

In addition, in areas that Ukraine has recaptured, residents are still recovering bodies of killed civilians, Donetsk Gov. Pavlo Kyrylenko said.

“Over the past 24 hours alone, in three de-occupied towns and villages, we found abandoned bodies of Ukrainian civilians,” Kyrylenko said.

Ukraine’s Interior Minister Denys Monastyrskiy said Sunday that Russian forces were mining territories they leave behind twice as densely as during the first months of the war.

Power outages were reported Sunday in the occupied Ukrainian city of Enerhodar, home to the closed Zaporizhzhia Nuclear Power Plant, Europe’s largest. Ukrainian and Russian officials traded blame for the shelling that caused the blackout.