A former leader of Iran's powerful Revolutionary Guard said Friday that the Islamic Republic should consider seizing a British oil tanker in response to authorities detaining an Iranian oil tanker off the coast of Gibraltar.
The comments by Mohsen Rezaei came amid heightened tensions over Iran's unraveling 2015 nuclear deal with Western powers, which the U.S. withdrew from last year.
"If England does not release the Iranian oil tanker, the duty ... [of Iran] is to respond and seize one English oil tanker," he said in a tweet.
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In recent days, Iran has broken through the limit the nuclear deal put on its stockpile of low-enriched uranium and plans on Sunday to boost its enrichment. In the past months, the U.S. has rushed thousands of additional troops, an aircraft carrier, B-52 bombers and advanced fighter jets to the region.
Rezaei led the elite Guard during Iran's 1980s "Tanker War" in the Persian Gulf targeting the oil trade of the U.S. and its Arab allies.
It was a striking comment from Rezaei, one that current officials have yet to make.
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Iran's Foreign Ministry spokesman earlier called on the U.K. to release the tanker.
Authorities in Gibraltar intercepted the supertanker on Thursday, saying they believed it to be breaching European Union sanctions by carrying a shipment of Iranian crude oil to Syria. Spanish authorities said the seizure came at the request of the U.S.
A spokesman for the government of Gibraltar, who wasn't authorized to be identified by name in media reports, said that all 28 crew members remain on the vessel while being interviewed as witnesses and not questioned under criminal procedures.
The crew is comprised of mainly Indian, Pakistani and Ukrainian nationals, he said.
On Friday, the Gibraltar Chronicle quoted Attorney General Michael Llamas saying that the British overseas territory's Supreme Court had granted an extension to July 19 to detain the supertanker following a Friday afternoon hearing.
Calls and e-mails to the court weren't immediately answered.
U.S. national security adviser John Bolton tweeted that the ship's seizure was "excellent news."
"America & our allies will continue to prevent regimes in Tehran & Damascus from profiting off this illicit trade," Bolton added.
The vessel likely carried just over 2 million barrels of Iranian crude oil, the data firm Refinitv said. Tracking data showed that the tanker made a slow trip around the southern tip of Africa before reaching the Mediterranean, it said.
Meanwhile, fears over a miscalculation sparking a wider conflict in the Persian Gulf have grown. Oil tankers near the Strait of Hormuz have been targeted in mysterious attacks, which the U.S. says Iran is behind, an accusation denied by Tehran. Last month Iran shot down a U.S. surveillance drone.
Ayatollah Mohammad Ali Movahedi Kermani, an adviser to Iran's supreme leader and Tehran's Friday prayer leader, brought up the drone shootdown during prayers.
He said the reason that the U.S. did not attack Iran after was because Trump fears Iran's ballistic missile stockpile.
"When Iranian missiles are able to hit a stealth drone thousands of feet in the air, how easy would it be to hit an aircraft carrier in the sea?" he asked.
German Foreign Ministry spokesman Rainer Breul was asked at a government briefing Friday about Iran's threat to ramp up uranium enrichment starting Monday.
"We have taken note of this Iranian announcement," Breul said. "We strongly urge Iran not to take this step."
He said if Iran does proceed, the nuclear agreement itself determines the next measures. "We are in close contact with other participants of the (Joint Comprehensive Plan of Action) on this," he said.