ISTANBUL (AP) — The first grain ship to leave Ukraine and cross the Black Sea under a wartime deal passed inspection Wednesday in Istanbul and headed on to Lebanon. Ukraine said 17 other vessels were “loaded and waiting permission to leave,” but there was no word yet on when they could depart.

A joint civilian inspection team spent three hours checking the cargo and crew of the Sierra Leone-flagged ship Razoni, which left Odesa on Monday carrying Ukrainian corn, a U.N. statement said.

The Joint Coordination Center team included officials from Ukraine, Russia, Turkey and the United Nations, who signed deals last month to create safe Black Sea shipping corridors to export Ukraine’s desperately needed agricultural products as Russia’s war on its neighbor grinds on.

Ukraine is a major global grain supplier but the war had blocked most exports, so the July 22 deal aimed to ease food security around the globe. World food prices have been soaring in a crisis blamed on the war, supply chain problems and COVID-19.

Although U.S. Secretary of State Antony Blinken called Razoni’s journey a “significant step,” no other ships have left from Ukraine in the past 48 hours and no explanations have been given for that delay.

A U.N. statement said inspectors “gained valuable information” from the Razoni’s crew about its voyage through the Black Sea maritime humanitarian corridor and the coordination center was “fine-tuning procedures.”

The Turkish Ministry of National Defense tweeted a picture of an inspector reaching into the Razoni’s hold and touching some of its 26,527 tons of corn for chicken feed. The Razoni’s horn rang out as the inspectors left the ship, and then it headed off to Lebanon.

The checks seek to ensure that outbound cargo ships carry only grain, fertilizer or food and not any other commodities, and that inbound ships are not carrying weapons.

An estimated 20 million tons of grain — most of it said to be destined for livestock — has been stuck in Ukraine since the start of the 6-month-old war. Ukraine’s top diplomat said Wednesday that more ships are ready to carry much-needed grain and food out of the country’s Black Sea ports.

“Further ships are already ready for departure. They will depart from the ports that are part of the grain initiative in accordance with the agreed schedule, and we hope that everything will work out and the Russian Federation will not take any steps that would destroy these agreements,” Foreign Minister Dmytro Kuleba said at a joint press conference in Kyiv with his Estonian counterpart.

Kuleba said the U.N.-backed deal “is beneficial to Ukrainian farmers, it is beneficial to the Ukrainian economy, and it is beneficial to the world.”

“It is now Ukraine that is, literally, saving the world from further growth in food prices and from hunger in individual countries,” he said.

Still, a Black Sea voyage entails significant risks because of the war. Two civilian ships hit explosive devices there last week near the Danube River’s Bystre estuary, according to Bridget Diakun, a data reporter at Lloyd’s List, a global shipping publication.

Analysts say authorities’ first priority is bringing out vessels that have been stuck for months at the three Ukrainian ports covered by the deal. Sixteen ships loaded with grain have been stuck at the ports of Odesa and Chernomorsk since Russia’s invasion, according to Lloyd’s List.

Even slower than that is the effort to bring ships into Ukraine’s ports to extract the millions of tons of grain in storage.

Insurance brokers are being “cautious, slow, so far,” said David Osler, insurance editor at Lloyd’s List. “At this stage, everyone’s hesitant.”

Grain stockpiles are expected to keep growing. Despite the war, Ukrainian Prime Minister Denys Shmyhal estimated his country would harvest up to 67 million tons of grain this year, up from 60 million tons last year.

A senior official from a leading Ukrainian farm association reckoned Ukraine would have about 50 million tons of grain for export this year.

Before the war, Ukraine exported around 5-6 million tons of grain per month, according to Denys Marchuk, the deputy head of the All-Ukrainian Agrarian Council. He said Ukrainian authorities are hoping to include more Black Sea ports in the export deal.

In other news Wednesday:

— Russian forces kept up their bombardment of the southern Ukrainian port city of Mykolaiv. Regional Gov. Vitaliy Kim said the shelling damaged a pier, an industrial enterprise, residential buildings, a garage cooperative, a supermarket and a pharmacy. The mayor of Mykolaiv, Oleksandr Sienkevych, told The Associated Press that 131 civilians have died so far in the city from Russian shelling and 590 others have been seriously injured.

— The Ukrainian military said Ukrainian forces pushed back over a dozen Russian assaults in the key eastern province of Donetsk and claimed that none of the Russian attempts to advance over the previous 24 hours were successful. Still, Russian shelling killed at least four civilians in Donetsk province, Ukraine’s presidential office said. President Volodymyr Zelenskyy has ordered all those in the embattled province to evacuate as soon as possible.

— The U.N. chief said he’s appointing a fact-finding mission in response to requests from Russia and Ukraine to investigate an explosion at a POW prison in a separatist region of eastern Ukraine that reportedly killed 53 Ukrainian prisoners of war and wounded another 75. U.N. Secretary-General Antonio Guterres told reporters that he doesn’t have authority to conduct criminal investigations but does have authority to conduct fact-finding missions. Both sides said the assault last Friday was premeditated with the aim of covering up atrocities.

— Moscow has drastically cut how much gas it sends to Europe, igniting fears that it could stop sending the much-needed fuel. All across Europe, nations are rushing to cut energy use this summer so they can fill up gas storage tanks for the cold winter ahead.

Robert Badendieck and Mehmet Guzel in Istanbul, Aya Batrawy in Dubai, Joanna Kozlowska in London and Edith Lederer in New York contributed to this report.