KYIV, UKRAINE — Wheat futures soared as Russia continued its nightly attacks of Ukrainian ports and threatened all ships heading for Ukrainian waters, Reuters reported.

US wheat futures jumped an additional 1.5% in the early hours of July 20 after jumping 8.5% on July 19, the biggest single-day rise since the early days of Russia’s invasion in February 2022.

Since pulling out of the Black Sea Grain Initiative on July 17, Russia has attacked ports in Odesa, Mykolaiv and Chornomorsk, causing damage to grain terminals and port infrastructure. The initiative had allowed for the safe passage of 33 million tonnes of grains and other foodstuffs from Ukrainian ports.

Attacks on July 20 hit residential buildings in Mykolaiv, injuring at least 19, Reuters said.

Russia’s military said it would consider all ships heading for Ukrainian waters to be potentially carrying weapons and their flag countries as parties to the war on the Ukrainian side.

“We believe that this is a coordinated effort to justify any attacks against civilian ships in the Black Sea and lay blame on Ukraine for these attacks,” White House National Security Council spokesperson Adam Hodge said.

Ukraine is hoping to restart exports without Russia’s participation and said on July 19 that it was setting up an alternative route via waters of Romania.

The grain initiative was brokered in July 2022 by Turkey and the United Nations. Russia in recent weeks had threatened to not extend the deal unless a series of demands, including the removal of obstacles to Russian grain and fertilizer exports, were met.

In the five months after Russia invaded Ukraine on Feb. 24, 2022, exports out of Ukraine were blockaded, causing grain prices to soar to near record highs and leading to food insecurity. Ukraine is a leading exporter of wheat, corn, barley and sunflower oil.