More than 1,000 merchant sailors are stranded in the Sea of Azov as Russia’s war in Ukraine rages around them, shipping officials said Thursday.

The sailors are attached to some 140 ships and represent 20 different nationalities, Seatrade Maritime News reported.

“We know of one remaining ship with 20 seafarers on board which has just three days of supplies left and it’s unsafe for them to leave the ship or for the ship to sail,” said Guy Platten, secretary-general of the International Chamber of Shipping.

Stephen Cotton, general secretary of the International Transport Workers Federation — a union representing merchant sailors — described how there is competition for food and called the situation “very dire,” especially for ships still in Ukrainian ports.

“I think we have to recognize there’s competition for food depending on which ports you’re in and where you are on the coast,” he said on a briefing call Thursday. “It is literally a matter of life and death for some of those Ukrainians still locked in defending their cities, and you can imagine that their first thought is not going to be to resupply ships or foreign nationals at anchor.”

“We have got an agreement with the industry that we can send people home but at the moment, if you’re in the worst parts of war-torn Ukraine, there’s no ability to get off the vessels and move,” added Cotton.

Platten added that getting ships to safety through the Sea of Azov would prove difficult, given the mines and sunken barges that litter the wartime ports.

“Until both countries, in particular Russia, agree to recognize that these foreign nationals are hostages to the situation, we can’t recommend they move, so they’re having to stay on board the vessel and then the challenge becomes about supplies,” Cotton said.