Grain shipments from Ukraine’s port of Odesa resumed Monday, the first since Russia invaded its neighbor in late February.

The Sierra Leone-flagged cargo ship Razoni was the first to leave port, carrying more than 26,000 tons of corn bound for Lebanon. In a statement, Turkey’s defense ministry said other unspecified ships would also depart Ukraine on Monday.

Turkey and the United Nations brokered an agreement with Russia and Ukraine in late July to get grain exports going again amid a global food crisis that the United Nations says has been worsened by Russia’s invasion of Ukraine.

The deal calls for safe passage of cargo ships traveling from ports in southern Ukraine through waters in the Black Sea that Russia has controlled since its invasion of Ukraine.

Ukrainian Foreign Minister Dmytro Kuleba welcomed the resumption of exports from Odesa.

“The day of relief for the world, especially for our friends in the Middle East, Asia, and Africa, as the first Ukrainian grain leaves Odesa after months of Russian blockade,” Kuleba tweeted. “Ukraine has always been a reliable partner and will remain one should Russia respect its part of the deal.”

Kremlin spokesman Dmitry Peskov told reporters Monday the departure of the first ship is “very positive.”

A spokesman for U.N. Secretary-General Antonio Guterres said ensuring grain can reach global markets “is a humanitarian imperative.”

“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,” Stephane Dujarric said in a statement.

Dujarric added that the World Food Program plans to purchase 30,000 metric tons of wheat to load and ship out of Ukraine on a U.N.-chartered vessel.

Also Monday, Britain’s defense ministry assessed that Russian forces had made only slow progress during the previous four days as they mounted tactical assaults in the area northeast of Donetsk.

British say Russians make ‘slow progress’

The British ministry said Russia is also likely shifting “a significant number of its forces” from the northern part of the Donbas region in eastern Ukraine to southern Ukraine.

For several months, Russia has focused its efforts on the Donbas, which includes Donetsk and Luhansk provinces, after facing resistance on its approach to the Ukrainian capital, Kyiv. A reallocation of resources to the east helped Russia claim control of Luhansk in early July.

Russia’s Black Sea fleet headquarters struck

In southern Ukraine, a small explosive device carried by a makeshift drone hit the headquarters of Russia’s Black Sea fleet on the Crimean Peninsula on Sunday, wounding six people, local authorities said, while Ukraine said a Russian missile attack killed one of its richest people, a grain merchant.

There was no immediate claim of responsibility for the drone attack in the port city of Sevastopol, which forced cancellation of ceremonies for Russia’s Navy Day holiday. But the seemingly improvised, small-scale nature of the attack raised the possibility it was the work of Ukrainian insurgents in the territory seized by Russia in 2014.

The drone appeared to be homemade and the explosive device low-powered, the Black Sea Fleet’s press service said. Sevastopol is about 170 kilometers from the Ukrainian mainland, but it is unclear where the drone began its flight.

‘Not an accident’

Elsewhere in Ukraine, the mayor of the major port city of Mykolaiv, Vitaliy Kim, said a Russian attack killed one of Ukraine’s wealthiest men, Oleksiy Vadatursky, and his wife, Raisa. Vadatursky headed a grain production and export business.

An adviser to Ukrainian President Volodymyr Zelenskyy, Mykhailo Podolyak, said Vadatursky was specifically targeted.

It “was not an accident, but a well-thought-out and organized premeditated murder,” Podolyak said. “Vadatursky was one of the largest farmers in the country, a key person in the region and a major employer. That the exact hit of a rocket was not just in a house, but in a specific wing, the bedroom, leaves no doubt about aiming and adjusting the strike.”

Vadatursky’s agribusiness, Nibulon, includes a fleet of ships for sending grain abroad.

Some information for this report came from The Associated Press, Agence France-Presse and Reuters.