KYIV, UKRAINE — Wheat futures rose as much as 5% following Russia’s bombing of key Ukrainian cities including Kyiv, Bloomberg reported.

Russian President Vladimir Putin threatened more attacks, after accusing Ukraine of damaging a bridge connecting Crimea to Russia.

Russia first invaded Ukraine in February, but this was the first attack on Kyiv in months. The United Nations and Turkey brokered a deal in July allowing grain shipments on the Black Sea to restart following a five-month blockade. That deal is set to expire in about a month, and the intensifying conflict raises the question of whether the agreement will be extended, Bloomberg said.

Chicago wheat futures rose as high as $9.2425 a bushel. Prices have climbed about 20% this year. Corn and soybeans also each rose more than 1.5%. Paris milling wheat climbed the most in three weeks.

Russia also attacked Odesa, which is a major grain hub and one of the three ports covered by the export agreement. 

As of Sept. 24, a total of 211 ships carrying nearly 5 million tonnes of agricultural products had embarked from Ukraine’s southern ports since the July 22 agreement went into effect. Prior to Russia’s invasion of Ukraine on Feb. 24, Ukraine exported up to 6 million tonnes of grain per month.

Many poorer nations, particularly in Africa, rely on Black Sea wheat for their food needs.