Iran says UK-flagged tanker Stena Impero is now 'free to leave'

New audio reveals moments leading up to tanker's seizure02:41

(CNN)The British-flagged oil tanker Stena Impero is "free to leave," Iranian officials said Monday, marking the end of a two-month standoff between Tehran and London over the detained vessel.

Iran's government spokesperson, Ali Rabiei, said that the legal process relating to the ship's seizure had been concluded and it was free to sail on to its destination, according to the country's semi-official Fars News Agency.

Rabiei did not say when the tanker would actually commence its voyage or re-enter international waters.

Erik Hanell, president and CEO of Stena Bulk, which owns the Stena Impero, told CNN Monday that the tanker is still in the port of Bandar Abbas, in the Persian Gulf, where it was initially seized by Iranian Revolutionary Guard (IRGC) forces. "We have no further information about it," Hanell said.

This announcement comes a day before UK Prime Minister Boris Johnson and Iranian President Hassan Rouhani are due to meet on the sidelines of the United Nations General Assembly in New York.

But the conciliatory mood may be short-lived. On Sunday, Johnson accused Iran of being behind the September 14 attack on Saudi oil facilities, reported the UK's PA Media news agency.

"The UK is attributing responsibility with a very high degree of probability to Iran for the Aramco attacks. We think it very likely indeed that Iran was indeed responsible," he told reporters on a flight to New York.

Johnson said he wanted to "deescalate tensions," but did not rule out military action if asked to take a role by Saudi Arabia or the United States, PA reported.

IRGC forces captured the Stena Impero in the Strait of Hormuz on July 19 amid increasing hostility between Tehran and the West. Twenty-three crew members -- none of them British -- were on board.

While the tanker was sailing under a UK flag, the company that operates it is headquartered in Sweden. Earlier this month, seven Indian crew members aboard the tanker were released.

The ship was seized two weeks after the UK detained an Iranian tanker off the coast of Gibraltar, a British overseas territory on the edge of southern Spain. Gibraltar authorities released that ship in late August, despite eleventh-hour efforts by the United States to halt the move.

CNN'S Sara Mazloumsaki and Helena de Moura reported from Atlanta. Tara John wrote from London.

By Tamara Qiblawi, CNN >>