Last week, Russian President Vladimir Putin vowed retaliation against Kyiv's maritime drone attacks on Moscow's "shadow fleet" tankers thought to be used to export oil, which Kyiv says is Russia's main source of funding for its almost four-year-old war.
The attack on Friday came hours after Turkish President Tayyip Erdogan told Putin that a limited ceasefire for energy facilities and ports could be beneficial.
Ukrainian President Volodymyr Zelenskiy posted photos which showed a large fire burning aboard a ship in the port of Chornomorsk in Odesa region, with firefighters tackling the blaze.
"This proves once again that Russians not only fail to take the current opportunity for diplomacy seriously enough, but also continue the war precisely to destroy normal life in Ukraine," he said.
That vessel's owner, Cenk Shipping, said the Cenk T vessel had been subject to attack around 4pm Ukraine time.
There were no casualties among the crew, and damage was limited, it added.
Reuters verified the moment of the attack seen on a video published on X. The vessel in the clip matched Cenk T, and the cranes and buildings matched satellite imagery of the Chornomorsk port.
Fabian Hinz, research fellow for defence and military analysis at the International Institute for Strategic Studies, said the weapon seen was a Russian Geran-2 drone in its loitering configuration.
Russia's defence ministry did not immediately reply to a Reuters request for comment.
"The strike is aimed at civilian logistics and commercial shipping," Ukraine's Deputy Prime Minister Oleksiy Kuleba said.
Russia attacked Ukrainian ports with drones and ballistic missiles, Kuleba added.
He said that one employee of a private company had been injured in a separate attack on Odesa port, and that a cargo loader had been damaged there.
Ukraine's navy spokesperson told Reuters that three vessels were damaged in total, all Turkish-owned. But the spokesperson did not provide additional details.
Turkey's foreign ministry confirmed damage in the Chornomorsk port, adding that there were no reports of injured Turkish citizens.
Reuters was able to verify the vessel by the design and name of the bow that matched file imagery of the Cenk T vessel.
"We reiterate the need for an arrangement whereby, in order to prevent escalation in the Black Sea, attacks targeting navigational safety as well as the parties' energy and port infrastructure are suspended," the ministry's statement said.
The three large Black Sea ports in the Odesa region are a key economic artery for Ukraine, which is a major commodities exporter.
In addition to the attacks on Moscow's "shadow fleet" tankers, Ukraine has ramped up pressure on Russia by hitting targets in the Caspian Sea this week, including vessels allegedly carrying military equipment and a major oil rig.
