The landmark deal signed by Moscow and Kyiv on Friday is seen as crucial to reining in global food prices and would allow certain exports to be shipped from Black Sea ports, including the hub of Odessa.

“The enemy attacked the Odessa sea trade port with Kalibr cruise missiles,” Ukraine’s Operational Command South wrote on the Telegram messaging app. Two missiles hit infrastructure at the port, while another two were shot down by air defence forces, it said.

Ukraine’s foreign ministry called on the United Nations and Turkey, which mediated Friday’s deal, to ensure that Russia fulfils its commitments and allows free passage in the grain corridor.

Russia’s defence ministry did not immediately reply to a Reuters’ request for comment.

A blockade of Ukrainian ports by Russia’s Black Sea fleet since Moscow’s Feb 24 invasion of its neighbour has trapped tens of millions of tonnes of grain and stranded many ships. This has worsened global supply chain bottlenecks and, along with Western sanctions on Russia, stoked food and energy price inflation.

Friday’s export deal seeks to avert famine among tens of millions of people in poorer nations by injecting more wheat, sunflower oil, fertiliser and other products into world markets including for humanitarian needs, partly at lower prices.

Senior UN officials, briefing reporters on Friday, said the deal was expected to be fully operational in a few weeks and would restore grain shipments from the three reopened ports to pre-war levels of 5 million tonnes a month.

Under the deal, Ukrainian officials would guide ships through safe channels across mined waters to three ports, including Odessa, where they would be loaded with grain.

Moscow has denied responsibility for the crisis, blaming Western sanctions for slowing its own food and fertiliser exports and Ukraine for mining the approaches to its Black Sea ports.