Iranian tanker crew interviewed as witnesses in Gibraltar

LONDON - The crew on a giant Iranian oil tanker detained in Gibraltar are being interviewed as witnesses, not criminal suspects, in an effort to establish the nature of the cargo and its ultimate destination, a spokesman for the British territory said Friday.

Meanwhile Iran demanded that Britain immediately release the vessel, accusing it of acting at the bidding of the United States.

A senior foreign ministry official "described the UK move as unacceptable" in a meeting with British ambassador Rob Macaire, who had been summoned to hear a formal protest, the ministry said in a statement.

He "called for the immediate release of the oil tanker, given that it has been seized at the request of the US, based on the information currently available", the statement added.

The secretary of Iran's Expediency Council, a key advisory and arbitration body, warned that if Britain failed to release the tanker, Iran would be forced to take tit-for-tat action against a British vessel.

"In its 40-year history, the Islamic revolution has never been the source of any tension but in the face of arrogance, we have never hesitated to respond," said council secretary Mohsen Rezai.

"If Britain does not release the Iranian oil tanker, the relevant authorities will be duty-bound to take reciprocal action and seize a British oil tanker."

Authorities in Gibraltar said they suspected the tanker was carrying crude oil to the Baniyas refinery in Syria in violation of EU sanctions.

The European Union has had sanctions in place for years that prohibit sales of oil to Syria. Europe does not have broad sanctions in place against Iran, but the United States does, driving Tehran off of mainstream oil markets in recent months and forcing it to seek unconventional outlets to sell its oil.

Shipping data suggests the tanker was carrying Iranian oil loaded off the coast of Iran, although its documents say the oil is from neighbouring Iraq.

'Maritime banditry'

Iran's complaint about the seizure dispelled any doubt over the ownership of the vessel, which is registered as managed by a company in Singapore.

British Royal Marines abseiled onto the Grace 1 tanker on Thursday, seizing it and landing a helicopter on the moving vessel in pitch darkness.  It was impounded in the British territory on the southern tip of Spain after sailing around Africa, the long route from the Middle East to the mouth of the Mediterranean.

A Gibraltar spokesman said the 28-member crew, who have remained on board the supertanker, were mainly Indians with some Pakistanis and Ukrainians. Police and customs officials remained on board the vessel to carry out their investigation, but the Royal Marines were no longer present.

If officials in Gibraltar have not fully established the nature of the cargo or the final destination, they could in the coming days ask a court for permission to hold the vessel for longer.

The detention of the 330-metre (1,000-feet) Grace 1 comes at a sensitive time in Iran-EU ties as the bloc mulls how to respond to Tehran announcing it is poised to breach the uranium enrichment limit it agreed to in a troubled 2015 nuclear deal.

The move could escalate a confrontation between Iran and the West that saw the United States call off air strikes minutes before impact last month.

The ship was detained 2.5 miles (four kilometres) south of Gibraltar in what it considers British waters, although Spain, which lays claim to the territory, says they are Spanish.

Iran insists the vessel was intercepted in international waters and the foreign ministry official accused Britain's Royal Navy of taking action "tantamount to martime banditry".

"Britain has no right to impose its own unilateral sanctions or those of the European Union in an extraterritorial manner against the other countries," the official said.

The Gibraltar authorities say the tanker was boarded when it slowed down in a designated area used by shipping agencies to ferry goods to vessels.

"We have reason to believe that the Grace 1 was carrying its shipment of crude oil to the Banyas refinery in Syria," Gibraltar's Chief Minister Fabian Picardo said.

At US request

In a statement, Britain's Foreign Office said: "We welcome this firm action by the Gibraltarian authorities, acting to enforce the EU Syria sanctions regime".

Spanish Foreign Minister Josep Borrell told reporters the vessel was detained at the request of the United States.

European Union sanctions against war-torn Syria have been in force since late 2011.

The 28-member bloc has imposed sanctions on Syrian officials including government ministers over their role in the "violent repression" of civilians.

It has frozen the assets of around 70 entities and introduced an embargo on Syrian oil, investment restrictions and a freeze on Syrian central bank assets within the EU.

The tanker's detention comes just days after Iran announced it would exceed the uranium enrichment limit set under the 2015 deal to allay concerns it might seek to develop a nuclear weapons capability, something it has always denied.

Tehran took the action in response to Washington abandoning the nuclear deal last year and hitting Iran's crucial oil exports and financial transactions with biting sanctions.

The unilateral move has sent tensions in the Gulf soaring as the administration of President Donald Trump forges ahead with a policy of "maximum pressure" against Iran in coordination with its Middle East allies Israel and Saudi Arabia.

White House National Security Advisor John Bolton, a champion of the hawkish policy towards Tehran, applauded the interception of the supertanker.

"Excellent news: UK has detained the supertanker Grace I laden with Iranian oil bound for Syria in violation of EU sanctions," Bolton tweeted.

According to specialised shipping trade publication Lloyd's List, which analyses vessel-tracking data, the 1997-built ship is laden with Iranian oil.

It reported that the ship loaded oil off Iran in April and sailed around the Cape of Good Hope in South Africa.