Seven sailors remain missing from a cargo ship that sank in the Black Sea off the Turkish coast on Tuesday, but search operations are continuing, the company operating the vessel has said.

"Our company isn't holding direct negotiations with the Turkish rescuers, but we are in contact with the Turkish side. There were 12 people on board the ship - 10 Ukrainians and two Russians. The rescuers have saved four and found one dead body, and continue looking for the rest," a Valship company spokesman told Interfax.

The dry cargo carrier Volgo Balt 199 sank in stormy seas near the village of Sile in Istanbul province.

At least two Turkish rescuers died while searching for the Volgo Balt 199's sailors.

Three of the crew members who have been rescued are Ukrainians, and one is Russian.

Valship's top management, said the company spokesman, was discussing monetary compensation for the families of the sailors who had died, but would make the final decision when the search is over.