The ship and its 2.1m barrels of crude oil have been sold to an unnamed buyer.
An Iranian government spokesperson announced the news on Monday, at a press conference in Tehran.
He said the ship’s buyer would decide on the tanker’s ultimate destination.
The tanker, previously known as the Grace 1, was earlier held for weeks off Gibraltar.
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It was stopped by authorities there on suspicion of violating EU sanctions on Syria.
The US has a warrant to seize the ship and has been warning other nations not to accept it.
Washington had attempted to detain the ship on the grounds it had links to Iran’s Islamic Revolutionary Guards Corps (IRGC), which it has designated a terrorist organisation.
Gibraltar said it could not comply with the warrant, issued by a federal court in Washington, because it was bound by EU law.,
US officials have claimed the oil was destined for a designated terrorist organisation.
The unsealed court documents argued Iran’s IRGC is the ship’s true owners through a network of front companies.
But authorities in Gibraltar said that, unlike in the US, the IRGC is not a designated terrorist organisation under EU, British or Gibraltan law.
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Gibraltar released the tanker on 15 August.
Iran has denied it was ever headed for Syria.
The ship had put its destination as Turkey, but later removed it.
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