The Grace 1, carrying 2.1 million barrels of oil, was seized by royal marines last month, as the UK claimed it was aiming to deliver oil to Syria in violation of EU sanctions.
Gibraltar’s chief minister Fabian Picardo reportedly lifted the detention order and said the government has received “formal written assurances” from the Iranian government that the ship will not discharge its cargo in Syria, according to local newspaper the Gibraltar Chronicle.
Britain said that Iran must abide by these assurances, and said it would not allow Iran or anyone to bypass European Union sanctions.
“We note the government of Gibraltar has received assurances from Iran that the Grace 1 will not proceed to Syria. Iran must abide by the assurances they have provided,” a British foreign office spokesperson said in a statement.
“We will not stand by and allow Iran – or anyone – to bypass vital EU sanctions on a regime that has deployed chemical weapons against its own people.
“There is no comparison or linkage between Iran’s unacceptable and illegal seizure of, and attacks on, commercial shipping vessels in the Strait of Hormuz and the enforcement of EU Syria sanctions by the government of Gibraltar.“
Earlier on Thursday, the US government applied to officially seize the ship from Gibraltar control.
According to Reuters, Gibraltar has said there are “no longer any grounds to keep Grace 1 detained”, and the US request to officially seize the ship was a matter for mutual legal assistance authorities who “will make an objective determination”.
The British detention of the Iranian ship prompted Iran to seize the British-flagged tanker the Stena Impero, which remains under the control of the country.
The Grace 1’s captain, an Indian national, and three officers were also released early on Thursday.
Gibraltar has said it expects the tanker to set sail soon.
Iran’s ambassador to the United Kingdom, Hamid Baeidinejad said the US faces “humiliation” with “its frantic last-minute efforts”.
In a tweet in Persian, he said: “With the efforts of the past few days, all the preparations and technical arrangements for the oil tanker to move to the high seas have been provided and the ship will soon leave the Gibraltar region.”
Iran’s foreign minister used stronger language, saying the US had failed in its attempts at “economic terrorism” in the form of sanctions and described efforts to seize the ship as a “piracy attempt”.
Javad Zarif said: “Having failed to accomplish its objectives through its economic terrorism – including depriving cancer patients of medicine – the US attempted to abuse the legal system to steal our property on the high seas.
“This piracy attempt is indicative of Trump admin’s contempt for the law.”
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