More than 40 larger commercial ships, with a capacity above 20,000 dwt are trapped in Ukrainian ports. The vast majority of them are bulkers.

Vessel tracking data available on the Signal Ocean and MarineTraffic data platforms show most vessels are in Black Sea ports still under Ukrainian control — Odessa, Chornomorsk, Mykolaiv, Yuzhnyy and Olvia.

Russian forces are understood to have captured Kherson, a big city with a relatively minor port by the Black Sea.

Kherson is just about 40 kilometres away from Mykolaiv and Olvia. A missile hit a Bangladeshi-controlled bulker in Olvia on Wednesday, the day the Russians captured Kherson, killing an officer.

The Russians have also captured Berdyansk, a small port at the Sea of Azov and were beleaguering Mariupol, another port city nearby.

Four attacks on vessels sailing or moored in Black Sea waters have been registered since war broke out on 24 February.

The Ukraine military shut down operations at its ports that day and hasn’t allowed vessels to leave. Russian forces, for their part, have declared the Sea of Azov to be closed to navigation.

Owners with vessels trapped in the region have been calling upon the international community to intervene to ensure the safety of their vessels.

The European Union (EU) and the US have urged the International Maritime Organisation (IMO) to hold an emergency session into the matter.