The first shipment of Ukrainian grain left the port of Odesa on Monday just over a week after Ukraine and Russia signed a deal with Turkey and the UN aimed at restarting grain exports from Ukraine's ports on the Black Sea.
Ukraine's infrastructure minister, Oleksandr Kubrakov, said on social media that the Sierra Leone-flagged cargo ship Razoni would head to Lebanon loaded with 26,000 tonnes of Ukrainian corn.
The five-month halt of deliveries from Ukraine - one of the world's biggest grain exporters - has contributed to soaring food prices, hitting the world's poorest nations especially hard.
Officials said the Razoni would make its way through a specially cleared corridor in the mine-infested waters of the Black Sea.
"It is expected in Istanbul on August 2," the Turkish foreign ministry said in a statement.
"It will then continue its journey after it has been inspected in Istanbul."
Other convoys would follow, respecting the maritime corridor and the agreed formalities, the statement added.
Last week Russian and Ukrainian officials gave the green light to a pair of twin deals brokered by Turkey and the UN to resume the grain exports.
The two countries signed two separate agreements with Turkey and the UN as they refuse to engage directly with each other.
Around 22 million tons of grain and other agricultural products have been stuck in Black Sea ports due to the conflict which started on 24 February when the Russian president Vladimir Putin ordered his country's armed forces into Ukraine.
Grain prices have fallen by two percent since it was announced the two sides were close to a deal.
UN Secretary-General Antonio Guterres welcomed the departure of the vessel.
A UN statement added: "The Secretary-General hopes that this will be the first of many commercial ships moving in accordance with the initiative signed, and that this will bring much-needed stability and relief to global food security especially in the most fragile humanitarian contexts.
"Ensuring that existing grain and foodstuffs can move to global markets is a humanitarian imperative," it added.
The World Food Programme also planned to purchase, load and ship an initial 30,000 metric tonnes of wheat out of Ukraine on a UN-chartered vessel, the statement said.
The European Union also hailed the ship's departure as a first step towards alleviating the food crisis.
Dmytro Kuleba, Ukraine's Foreign Minister, said the shipment would have global ramifications.
The Russian government described the shipment as very positive news
"As for the departure of the first ship, this is a good opportunity to test the effectiveness of the mechanisms that were agreed during talks in Istanbul," Kremlin spokesman Dmitry Peskov told reporters.