Sanctions and counter-sanctions following the invasion of Ukraine have sent waves of transactions going in both directions, forcing a sell-off of many Russian-owned ships and, at the same time, generating demand on the buying side to remedy Russia’s tonnage gap.

But a third group of vessels is caught in a double bind — specialised tonnage that had been flagged into the Russian trades by foreign owners to exploit a shortage of such ships in the Russian fleet, but that is now stuck there, unable to trade or leave.