This article is more than 1 year old

This article is more than 1 year old

Panama’s maritime authority has begun the process of withdrawing the registration of the oil tanker MT Riah, which ended up in Iranian waters after it disappeared from ship tracking maps in the strait of Hormuz on 14 July.

Panama began the flag-withdrawal process on Friday after an investigation determined the tanker had “deliberately violated international regulations” by not reporting any unusual situation, the authority said in a statement.

“We roundly condemn the use of Panamanian flagged ships for illicit activities,” it said.

Concern grows over oil tanker last seen off Iran Read more

Panama, which has the largest shipping fleet in the world, has recently withdrawn flags from dozens of vessels, some of which were operated by Iran. It is not clear which country or company owns and operates the Riah.

The latest development followed the British seizure of an Iranian oil tanker, Grace 1, which London suspected was violating EU sanctions on Syria.

Sanctions against the regime of Bashir al Assad regime were there to be enforced and international law upheld, the UK argued. There seemed little doubt, given its circuitous route, that the ship was bound for Syria.

Panama said the Grace 1 was removed from its registry on 29 May.

Iran’s supreme leader, Ayatollah Ali Khamenei, branded the ship’s seizure as “piracy,” and Iran threatened to retaliate.

On Friday it seized two British-linked ships in the strait of Hormuz. Iranian forces took control of the British-flagged Stena Impero, and directed it to the Iranian port of Bandar Abbas, where it remains. A second Liberian-flagged but British operated tanker, the Mesdar, was also detained for several hours by Iranian forces on Friday. It made a sudden diversion from its planned course, and began moving towards the Iranian coast before apparently turning off its tracking signal.

On Tuesday Iran’s semi-official news agency, ISNA, said the country’s navy came to the assistance of the MT Riah after it experienced mechanical problems.

US officials have said they are unsure whether the tanker was seized by Iran or rescued, creating a mystery at sea at a time of high tension in the Gulf.

The tracking report of the Riah from MarineTraffic.com showed the vessel began its journey near a port off the coast of Dubai, in the United Arab Emirates, on 5 July. It was then tracked near the coast of Ras al-Khaimah before changing course and travelling north towards Iranian waters, after which it stopped transmitting its signal on Sunday at about 4.30am local time (0100 BST).

Its last known location was in Iranian territorial waters near Qeshm Island, where the Revolutionary Guards have a base.

Earlier this month, Panama’s maritime authority said it would withdraw its flag from more vessels that violate sanctions and international legislation, following the removal of about 60 ships linked to Iran and Syria from the Panamanian registry in recent months.

Washington has called for greater security for ships in the Gulf.