Wheat prices jumped Monday morning after Russia’s weekend attack on the major Ukrainian port of Odesa. The missile strikes penetrated doubt in a UN-backed deal reached Friday to resume Ukraine grain exports, which have been piling up since Russia’s invasion, contributing to a global food crisis.

On the day of the deal, wheat futures had dropped to the lowest level since the start of the war. But less than 24 hours later, Russia’s strikes are shaking global confidence in the country’s commitment to the terms and were internationally condemned.

The Kremlin insisted the strikes hit military targets and won’t impact plans to resume grain exports. On Monday, Russian foreign minister Sergey Lavrov defended the strikes at a press conference during a visit to the Democratic Republic of Congo.

“There is nothing in the obligations that Russia took, including within the framework of the agreements signed on July 22 in Istanbul, which prohibit us from continuing the special military operation, destroying military infrastructure and other military targets,” Lavrov said.

Meanwhile, Ukraine said it is still committed to restarting those exports out of the Black Sea as soon as this week, in spite of the strikes. According to Ukrainian military, Russia launched four missiles at the port, two of which were shot down.

“We are discussing the formation of caravans of ships that will carry out the tasks and agreements reached and signed by Ukraine, Turkey, and the United Nations,” Odesa regional administration spokesperson Serhii Bratchuk said Monday. He added that demining of the port was not being explored as the risk of a Russian amphibian attack or seizure of the port still remained.

“The most important thing is that exports can and should go through the Black Sea, and I hope that we will be able to implement this,” he added.

Ukraine is known as the breadbasket of Europe and is the world’s fifth-largest wheat exporter and fourth-largest corn exporter. Russia blocking its ports has sent food prices soaring worldwide.

The Associated Press contributed to this report.