An Iranian oil tanker bound for Greece has abruptly changed course and will instead make port in Turkey, according to the Associated Press.

The ship Adrian Darya 1, formerly known as the Grace 1, is now on track to reach Mersin, Turkey, in roughly a week.

U.S. authorities believe the vessel, which is carrying $130 million worth of Iranian crude oil, is controlled by the Iranian Revolutionary Guard. The United States has classified the group as a terrorist organization. The Greeks said the ship could not dock at their ports after facing pressure from the U.S, the wire service reported.

The tanker previously was held in detention at Gibraltar over suspicions that it was smuggling oil to Syria in violation of European Union sanctions on the country, according to Reuters.