Tehran((ANN)-Iran said Sunday it has seized an Iraqi oil tanker in the Persian Gulf for allegedly smuggling fuel, according to the official IRNA news agency.

It remains unclear the nationality of the seized vessel. Seven crewmen of different nationalities were detained.

In a statement, the elite Islamic Revolutionary Guards Corps (IRGC) said the vessel was captured near the Farsi Island. The tanker was carrying 700,000 liters of “smuggled fuel” and was taken to the Bushehr port, the IRGC statement said.

“The seizure of the oil tanker was in coordination with Iran’s judiciary authorities and based on their order,” Fars quoted the Guards commander Ramezan Zirahi as he as saying.

“The IRGC’s naval forces have seized a foreign oil tanker in the Persian Gulf that was smuggling fuel for some Arab countries,” the Guards commander Ramezan Zirahi told state TV.

“The boats of the IRGC navy were patrolling the area to control traffic and detect illicit trade when they seized the tanker,” Fars quoted Zirahi as saying, adding that the seizure was in coordination with Iran’s judicial authorities.

Iran, which has some of the world’s cheapest fuel prices due to heavy state subsidies and the fall of its currency, has been fighting rampant fuel smuggling by land to neighbouring countries and by sea to Gulf Arab states.

Tensions have risen between Iran and the West since last year when the United States pulled out of an international agreement which curbed the Islamic Republic’s nuclear programme in return for an easing of economic sanctions on Iran.

Last month, Iran seized a British-flagged tanker in the strategic Strait of Hormuz, in a retaliatory action for the seizure of an Iranian vessel by Gibraltar – a British oversees territory.

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Fears of a Middle East war with global repercussions have risen since Trump withdrew from the nuclear deal and revived a panoply of sanctions meant to push Tehran into wider security concessions.

Iran has retaliated by resuming uranium enrichment seen in the West as a potential conduit to developing an atom bomb. But it faces severe economic damage under intensified US sanctions designed to strangle its vital oil trade.

After several attacks in May and June on oil tankers – blamed by Washington on Tehran, which denied responsibility – Trump has been trying to forge a military coalition to secure Gulf waters, though European allies have been loath to join for fear of provoking open conflict.

European parties to the deal – Britain, France and Germany – have instead appealed for diplomatic moves to defuse the crisis and have been trying to salvage the pact by exploring ways to shield Iran’s economy from US sanctions.

Tehran has called on them to accelerate their efforts or it will further decrease its commitments to the agreement.

Britain said on July 25 that it had started sending a warship to accompany all British-flagged vessels through the Strait of Hormuz.