The US Department of Justice has revealed a seizure warrant for the supertanker Grace 1 just a day after Gibraltar released the ship.
The move by the US on Friday followed an attempt earlier this week to persuade the Gibraltar supreme court to keep the ship in detention.
Grace 1 has been at the heart of recent tensions between Iran and the UK since British Royal Marines seized the ship in July. Iran retaliated by seizing a UK-flagged vessel, the Stena Impero, an act UK has said was unlawful.
A civil forfeiture complaint accompanying the US warrant alleged the tanker was part of a scheme by Iran to finance its Revolutionary Guards unit through sales of oil to Syria.
It cited evidence that the ship had been destined for Port Banias in Syria, including a “confidential source” who provided information before Grace 1’s seizure in Gibraltar.
“Charts and electronic equipment recovered from onboard the Grace 1, WhatsApp messages recovered from crewmembers’ mobile devices, and crewmembers’ statements” showed Grace 1 was headed for Syria, the complaint claimed.
Iran has denounced the detention of Grace 1 as being part of an “economic terrorism” campaign launched by President Donald Trump, who pulled the US out of a landmark deal with Tehran struck by the Obama administration. It has also denied the vessel was carrying oil to Syria.
The Trump administration has ramped up sanctions on Iran, causing damage to its economy, but has thus far failed to reduce the country’s oil exports to zero or force its leadership to the negotiating table.
Earlier this month, the US took the dramatic step of sanctioning Mohammad Javad Zarif, Iran’s foreign minister, who on Thursday called the Grace 1’s seizure a “piracy attempt”.
The tanker has not yet left Gibraltar waters, with the ship’s captain reportedly unwilling to continue in command of the vessel, but it is not clear if the US will be able to stop its departure.
Fabian Picardo, Gibraltar’s chief minister, said on Thursday Iran had given a “written assurance” that Grace 1 would not travel to Syria and that US efforts to detain the ship would need to go through diplomatic channels.
“That is a matter for our independent Mutual Legal Assistance authorities who will make an objective, legal determination,” he said.
A justice department spokeswoman confirmed the US was seeking the seizure of the ship again after its release. The warrant for the tanker, its oil and $1m linked to the ship was filed in federal court in Washington DC on Friday.
The UK had alleged Grace 1 was heading to Syria and in violation of EU sanctions when it seized the ship in July. Iran’s subsequent seizure of the Stena Impero in the Strait of Hormuz heightened concerns about the maritime security of global oil supply in the strategic Gulf waterway as tensions rise between Iran and the US.
Tehran said it detained the Stena Impero because it violated international maritime regulations by causing pollution in the Strait of Hormuz, switching off tracking devices to avoid Iranian forces and colliding with a fishing boat.
The detention caused the UK to deploy a second warship to the region last month to provide additional security for British-flagged ships. The UK recently said it would join the international maritime initiative, set out by the US, to improve security through the Strait.
Despite this, security has remained a concern. People in the shipping industry and a US government official have said there were concerns that Iran could be trying to target UK nationals.
Earlier this week, the State Department warned that any crew members of vessels assisting the Islamic Revolutionary Guard Corps by transporting Iranian oil would be barred from entering the US. It referred questions on its recent bid to seize the tanker to the justice department.
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