Iran detained the Stena Impero on July 19 on allegations that it had violated maritime regulations while passing through the Strait of Hormuz.
Last Wednesday, Iran claimed that it released seven crew members of the oil tanker.
The Iranian officials have ruled out any link between Stena Impero's case and British seizure of the Iranian supertanker Grace 1 off the coast of Gibraltar.
Grace 1, renamed as Adrian Darya 1, was released by Gibraltar authorities on August 16. (Xinhua/ANI)