Iran should seize a British oil tanker if an Iranian tanker detained off Gibraltar earlier this week is not released immediately, two influential Iranian figures said in tweets on Friday.
British Royal Marines seized the supertanker Grace 1 on Thursday for trying to take oil to Syria in violation of EU sanctions, a dramatic step that drew Tehran's fury and could escalate its confrontation with the West.
“If Britain does not release the Iranian oil tanker, it is the authorities duty to seize a British oil tanker," said Revolutionary Guards Major General Mohsen Rezaee, who is also secretary of Iran's Expediency Council, a powerful state body.
"Islamic Iran in its 40-year history has never initiated hostilities in any battles but has also never hesitated in responding to bullies," Rezaee said on his Twitter account.
Rezaee has in the past also suggested taking American servicemen hostage in the Persian Gulf and demanding money for their release.
Another influential Iranian figure who was in the nuclear negotiating team, Mahdi Mohammadi also threatened British ships on Twitter.
Iranian Foreign Ministry spokesman Abbas Mousavi said on Thursday that the Iranian oil tanker was carrying crude oil from Iran, according to the state news agency IRNA.
The Grace 1 was impounded off Gibraltar, a 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.
While the European Union has banned oil shipments to war-torn Syria, a close ally of Iran, since 2011, it had never seized a tanker at sea. Unlike the United States, Europe does not have broad sanctions against Iran.