Gibraltar’s chief minister has said he will allow a detained Iranian oil tanker to be released after Tehran gave the territory’s government an assurance that it would not allow its cargo to be discharged in Syria.
But Fabian Picardo acknowledged that his decision could yet be overturned after the US Department of Justice (DoJ) launched a challenge in the territory’s courts.
He said that in light of this assurance “there are no longer any reasonable grounds for the continued legal detention” of the vessel and he was prepared to allow it to be released.
He acknowledged that the DoJ had effectively challenged that decision and said mutual legal assistance authorities would make “an objective, legal determination of that request”.
Earlier, Trump administration officials told the Guardian that the seizure request was consistent with wider efforts to intensify the effect of western economic sanctions on Iran and Syria.
A US official said the tanker case was significant because “it’s both an Iranian regime oil export and, in the judgment of HMG [the UK government], it’s an Assad regime oil import. We have an interest in the disruption of both of those, both for our overarching Iran policy and our Syria policy.”
The American action would appear to counteract efforts by the UK to calm tensions with Iran. British officials said they were notified in advance by the US of its intention to challenge the release of the tanker in the courts, but they would not say immediately when that had occurred.
In a separate development, the Gibraltar Chronicle reported that the captain and three officers of the Grace 1 had been released from arrest on Thursday. A Gibraltar government spokesman declined to comment.
British officials would not say whether the subject of the tanker came up. “The US is a close ally and we engage with them routinely on matters of national security,” a government spokesman said.
The Foreign Office said the “investigations conducted around the Grace 1 are a matter for the government of Gibraltar” and it could not comment further as the investigation was under way.
Grace 1 was seized by British Royal Marines off Gibraltar on 4 July on suspicion that it was taking 2.1m barrels of oil to Syria in breach of an EU arms embargo. At the time, Bolton hailed the seizure describing it as “excellent news”.
The seizure led to reprisals by Iran, including the capture of the British-flagged Stena Impero. Both incidents fuelled worsening hostilities between Iran and the west that began when Washington pulled out of an international agreement curbing Iran’s nuclear programme and reimposed economic sanctions.
Bolton, during his trip to the UK, made further diplomatic efforts to steer a post-Brexit UK further away from Europe on a range of issues including the Iran nuclear deal and the role of the Chinese technology firm Huawei.
Bolton is hoping that a Johnson administration will gradually adopt a foreign policy on Iran more independent of its two former EU partners Germany and France after Brexit, and closer to the policy of maximum economic pressure on Tehran imposed by Donald Trump.
This month Iran accused the US of engaging in “economic terrorism” against its people. The Iranian foreign minister, Mohammad Javad Zarif, warned Britain that acting in concert with the Trump administration would bring about a response from Tehran.
Zarif said: “Britain is an accomplice in US economic terrorism, and this complicity will definitely bring about consequences for them.”
Associated Press contributed to this report