UK voices to Iran 'extreme disappointment' over seized tanker

British Foreign Secretary Jeremy Hunt said he told his Iranian counterpart Saturday of his "extreme disappointment" after Tehran seized a UK-flagged tanker in the Gulf.

In a tweet, Hunt said he had spoken to Iranian Foreign Minister Javad Zarif "and expressed extreme disappointment that having assured me last Sat(urday) Iran wanted to de-escalate situation they have behaved in the opposite way".

"This has to be about actions not words if we are to find a way through. British shipping must and will be protected."

The foreign office in London said it summoned Iran's charge d'affaires on Saturday.

The diplomat was called in as European powers urged Iran to release the Stena Impero oil tanker it seized in the Strait of Hormuz on Friday.

The seizure of two ships by Iranian authorities "is of deep concern", said a statement by the EU's foreign affairs office, which represents the bloc's 28 member states.

"In an already tense situation, this development brings risks of further escalation and undermines ongoing work to find a way to resolve current tensions," the statement said.

"We urge the immediate release of the remaining ship and its crew, and call for restraint to avoid further tensions," it said, adding that "freedom of navigation must be respected at all times".

Meanwhile, the UK government's COBRA emergencies committee met late on Friday and was expected to meet again on Saturday.

The UK government warned vessels not to enter Gulf waters on Saturday.

"We remain deeply concerned about Iran's unacceptable actions which represent a clear challenge to international freedom of navigation," a government spokeswoman said following an overnight meeting after a night-time emergency meeting.

"We have advised UK shipping to stay out of the area for an interim period."

London-based maritime security risk analysts Dryad Global said the "dramatic escalation" by Iran was likely to have been a calculated move.

The interception was "likely to have been a pre-planned operation and intended for use at a time where Iran perceives there to be strategic narrative to be leveraged", it said.

The maritime experts said Iran was likely targeting what it perceived as the "junior" partner to the US.

"The UK will be forced to respond, but will find few avenues to do so, both militarily and diplomatically," the firm said.

The EU's plea came after bloc powers Germany and France condemned the taking of the Stena Impero and the seizing earlier this week of a smaller Panamanian-flagged tanker.

Berlin and Paris both underlined their solidarity with Britain.

The UK, Germany and France were the lead European powers that negotiated with Iran to curb its nuclear programme in a 2015 deal in return for the lifting of sanctions.

President Donald Trump has pulled the US out of the agreement and imposed sanctions to block Iran exporting its oil, much of which transits through the Strait of Hormuz.

Up to now, the UK, Germany and France had sought to keep the deal with Iran alive by setting up a trade mechanism not subject to the US sanctions, but rising military tensions in the Gulf have put that at risk.

Agencies contributed to this report.

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