A Russian-flagged tanker loaded with sunflower oil reported a drone attack off the Turkish coast on Tuesday, but its 13 crew members were unharmed, Turkey's maritime authority and the Tribeca shipping agency said.

The vessel, MIDVOLGA-2, reported coming under attack 80 miles (130 km) off the Turkish coast but did not make a request for assistance and was proceeding towards Turkey's Sinop port, Turkey's Maritime Affairs Directorate said on X.

Tribeca said the ship had been attacked by a drone. It was not immediately clear who had attacked the ship and Turkey's Maritime Affairs Directorate did not provide additional details.

The maritime authority said the ship was sailing from Russia to Georgia, while Tribeca said it was bound for Mersin. Both said the ship was now en route to Sinop without assistance.

"The necessary messages were conveyed to the relevant parties, including Ukrainian authorities," a Turkish official said when asked for comment, but gave no further details.

Turkish President Tayyip Erdogan said on Monday that attacks on commercial ships in the Black Sea were unacceptable, issuing a warning to "all related sides."

Ukrainian naval drones last week hit two tankers sanctioned by Kyiv and some of its Western allies in the Black Sea as they headed to a Russian port to load oil destined for foreign markets, as it attempts to pile pressure on Russia's oil sector.

NATO member Turkey has maintained cordial ties with Kyiv and Moscow throughout the war. It has provided military support to Ukraine, but refused to join Western sanctions on Moscow.

It has previously hosted three rounds of peace talks between the warring sides in Istanbul and repeatedly offered to host a leaders' meeting, saying an end to the war must be achieved now.

Ankara has also demanded navigational safety in the Black Sea, where it shares maritime borders with Russia and Ukraine.