An Iranian supertanker detained for the last month has left Gibraltar and is heading east into the Mediterranean Sea.
Data on Marinetraffic.com showed the Adrian Darya 1, which used to be called Grace 1, moving shortly before midnight.
The tanker slowly steered southeast toward a narrow stretch of international waters separating Morocco and the southern tip of the Iberian Peninsula.
The vessel was detained by Royal Marines last month.
Its next destination is thought to be Greece.
There was a last-ditch effort from the US to try and re-seize the vessel and its cargo, citing violations of US sanctions as well as money laundering and terrorism statutes.
However, Gibraltar rejected the request stating: "The EU sanctions regime against Iran - which is applicable in Gibraltar - is much narrower than that applicable in the US."
Gibraltar also says it has secured assurances from Tehran that the cargo will not go to Syria.
Analysts believe the release of the Iranian vessel could lead to the Stena Impero going free.
The British tanker was seized by Iranian forces in the Strait of Hormuz and remains held by the Islamic Republic.