Iran threatens to respond to UK detaining oil tanker

The tanker's seizure "will not be tolerated by us and will not go without a response," said Amir Hatami, as quoted by semi-official news agency ISNA and Tasnim news agency.

"This move is against international regulations and a kind of a maritime piracy," he added, speaking at a ceremony at Bandar Abbas port in southern Iran.

The 330-metre (1,000-feet) Grace 1, capable of carrying two million barrels of oil, was halted on Thursday by police and customs agencies in Gibraltar, a British overseas territory on Spain's southern tip.

Spain, which lays claim to the territory, says they are Spanish.

Iranian Deputy Foreign Minister Abbas Araghchi said the tanker was crossing the Strait of Gibraltar because its "high capacity" meant "it was not possible for it to pass through the Suez Canal". 

He insisted the tanker was intercepted in international waters and accused Britain's Royal Navy of committing "maritime piracy".

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

On Sunday, Iran denied that the tanker detained by Britain was carrying crude to Syria.

"The tanker was carrying Iran's oil... Contrary to what the British government claims, its destination was not Syria," said Araghchi at a press conference in Tehran.

"The port named in Syria does not even have the capacity for such a supertanker to dock. Its destination was somewhere else," he added.

On Friday, Gibraltar’s Supreme Court ruled that the tanker can be held for 14 more days, the territory's attorney general said.

The vessel's detention came at a sensitive time in Iran-EU ties as the bloc mulls how to respond to Tehran breaching the uranium enrichment limit it agreed to in the troubled 2015 nuclear deal.

On Saturday, fears were raised after a British oil tanker was reportedly "immobilised" for several hours in the Gulf .

Reports said the British-flagged supertanker called "Pacific Voyager" stopped moving for hours before changing its tracking signal to "not under command”.

But a United Kingdom Maritime Trade Operations (UKMTO) official said the tanker was “safe and well", debunking reports it had been seized by Iran after Iranian officials threatened to seize a British-flagged vessel.

The IRIB news agency quoted an unnamed official on Saturday that denied reports suggesting the "Pacific Voyager" had come to a halt in the Gulf.

The source dismissed the news as "fabricated".

A British shipping official has also denied the reports saying the supertanker stopped as a part of a routine procedure.

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.

Follow us on Twitter: @The_NewArab