The Sierra Leone-flagged Razoni set sail from Ukraine's Odesa port on Aug. 1 under a hard-won grain deal but did not unload in Lebanon as planned. Its location had not been clear in recent days as it has kept its transponder off.

Satellite imagery from Planet Labs PBC showed it at the Tartus port on Tuesday morning. A shipping source confirmed it had docked there and said it was unloading at least part of its cargo of corn in Syria.

The cargo of 26,000 tonnes of corn had originally been destined for Lebanon, which has been suffering an economic crisis that has plunged about half of its population into food insecurity.

However, the original buyer refused the delivery over quality concerns and the ship sailed to Turkey, docking in Mersin on Aug. 11 and unloading part of the cargo there.

When it set sail again the following day, it did not keep its transponder on.

Ukraine has previously accused Syria of importing at least 150,000 tonnes of grain it said was plundered from Ukrainian warehouses after Russia's invasion in February. Russia has denied stealing Ukrainian grain.

Kyiv cut off diplomatic ties with Damascus in June after Syria recognised the independence of the eastern regions of Luhansk and Donetsk.

Ukraine's ministry of transport said at the weekend that it was "not responsible for vessel and cargo after it has left the Ukraine, moreover after vessel's departure from (a) foreign port".

(Reporting by Maya Gebeily and Yoruk Isik; editing by Ed Osmond and Bernadette Baum)