Iran gave a stark warning to the US on Monday over further attempts to seize the Iranian oil tanker that set sail on Sunday, after it spent six weeks detained in Gibraltar.

The US Justice Department issued a federal warrant last week for the seizure of the supertanker — a move that was given short shrift from Tehran.

"Iran has given necessary warnings to American officials through its official channels... not to make such a mistake because it would have grave consequences," Iran's Foreign Ministry Spokesman Abbas Mousavi told reporters.

Iran had been in a standoff with the UK since Royal Marines seized the tanker, formerly known as Grace 1, off the coast of Gibraltar on July 4 as it headed for Syria. British authorities apprehended the vessel on suspicion of it shipping oil to Syria in breach of EU sanctions. The Supreme Court of the British territory of Gibraltar lifted its detention order last week, despite protests from the US. 

Also in July, Iran's Islamic Revolutionary Guard Corps impounded a British-flagged tanker in Gulf waters.

However, on Monday, the Iranian Foreign Ministry refuted suggestions it was a tit-for-tat move. "There is no connection whatsoever between these two vessels," spokesman Mousavi said.

The Grace 1, renamed the Adrian Darya 1, left anchorage off Gibraltar late on Sunday night and is currently en route to Kalamata, Greece, according to shipping data.

Cat and mouse

DW's Iran correspondent Theresa Tropper, who has recently returned from the Strait of Hormuz, a stretch between the Persian Gulf and the Gulf of Oman, says that the vessel's future remains unclear.

"Iran has never disclosed the destination of the tanker, but always saying it was not headed for Syria," she said.

Tropper, however, does see last month's seizure of the British tanker in the Gulf as retribution from Iran.

"The seizure of the British flagged tanker was an act of retaliation, that's for sure."

jsi/ng (AFP, Reuters)

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