Tehran has demanded the immediate release of the Grace 1 supertanker, which a detachment of royal marines boarded off the coast of Gibraltar on suspicion it was breaking European Union sanctions by carrying oil to Syria.

Hassan Rouhani called the seizure “mean and wrong” during a cabinet meeting, the official IRNA news agency reported.

“You [Britain] are an initiator of insecurity and you will understand its repercussions,” he warned, calling for the “full security” of international shipping lanes.

He added: “Now you are so hopeless that, when one of your tankers wants to move in the region, you have to bring your frigates [to escort it] because you are scared. Then why do you commit such acts? You should instead allow navigation to be safe.”

Tensions high as Trump approves new Iran sanctions: In pictures Show all 17 1 /17 Tensions high as Trump approves new Iran sanctions: In pictures Tensions high as Trump approves new Iran sanctions: In pictures Iran claims that in this picture released by Iran state TV, their surface-to-air missile is seen as it shoots down a US surveillance drone EPA Tensions high as Trump approves new Iran sanctions: In pictures This photo shows US RQ-4A Global Hawk unmanned surveillance drone. A drone of this model was shot down by Iran on Thursday 21 June AFP/Getty Tensions high as Trump approves new Iran sanctions: In pictures An oil tanker is on fire after it was subject to a suspected attacked at the Gulf of Oman on June 13. The US has blamed Iran for the attack Reuters Tensions high as Trump approves new Iran sanctions: In pictures Iran claims that in this picture released by Iran state TV, debris from the downed US drone is seen after it was recovered from Iranian waters AFP/Getty Tensions high as Trump approves new Iran sanctions: In pictures Smoke billows from an oil tanker after it was subject to a suspected attacked at the Gulf of Oman on June 13 Reuters Tensions high as Trump approves new Iran sanctions: In pictures US President Trump holds up a signed executive order to increase sanctions on Iran on 24 June AP Tensions high as Trump approves new Iran sanctions: In pictures Iranian President Rouhani stated in a televised address that the White House is "afflicted by mental retardation" following the increase in sanctions on 25 June EPA Tensions high as Trump approves new Iran sanctions: In pictures An Iranian navy boat tackles the fire on the Norwegian owned Front Altair oil tanker after it was hit in a suspected attack AFP/Getty Tensions high as Trump approves new Iran sanctions: In pictures Iran claims that in this picture released by Iran state TV, debris from the downed US drone is seen after it was recovered from Iranian waters AFP/Getty Tensions high as Trump approves new Iran sanctions: In pictures Smoke billows from an oil tanker after it was subject to a suspected attacked at the Gulf of Oman on June 13 Reuters Tensions high as Trump approves new Iran sanctions: In pictures A screenshot from a video released by the US Department of Defense that the US claims to show Iranian removing an unexploded limpet mine form the hull of the Japan-owned ship that was attacked in the Gulf of Oman on June 13 Getty Tensions high as Trump approves new Iran sanctions: In pictures An item reportedly found on the Japan-owned oil tanker that was attacked on June 13 in the Gulf of Oman AFP/Getty Tensions high as Trump approves new Iran sanctions: In pictures A handout photograph from the US Department of Defense shows a composite material that the US claim was left behind on the hull of the Japan-owned oil tanker following the removal of an unexploded limpet mine Getty Tensions high as Trump approves new Iran sanctions: In pictures A view from the cabin of an Iranian navy boat as it tackles the fire on the Norwegian owned Front Altair oil tanker after it was hit in a suspected attack EPA Tensions high as Trump approves new Iran sanctions: In pictures Release by US government A picture released by U.S. Central Command shows damage to the hull of the oil tanker Kokuka Courageous. The picture suggests that the ship is 'likely' to have been hit by a mine as the US Secretary of State Mike Pompeo moves to blame Iran for the suspected attack Reuters Tensions high as Trump approves new Iran sanctions: In pictures Smoke billows from an oil tanker after it was subject to a suspected attacked at the Gulf of Oman on June 13 Reuters Tensions high as Trump approves new Iran sanctions: In pictures Release by US government A picture released by U.S. Central Command shows damage to the hull of the oil tanker Kokuka Courageous. The pictures suggests that the ship is 'likely' to have been hit by a mine as the US Secretary of State Mike Pompeo moves to blame Iran for the suspected attack EPA

Meanwhile, Mohammad Javad Zarif, Tehran’s foreign minister, denied the supertanker belonged to Iran.

He said whoever owned the oil shipment and the vessel could pursue the case through legal avenues.

Iran had earlier summoned the British ambassador over what it called the “illegal interception” of the ship.

Mapping data from Refinitiv Eikon released at the time the tanker was seized indicated it sailed from Iran via a route around the southern tip of Africa, rather than going through the Suez Canal in Egypt.

The Grace 1 was documented as loading fuel oil in Iraq in December, though the Iraqi port did not list it as being in port and its tracking system was switched off.

If the 300,000-tonne tanker was confirmed to be transporting Iranian crude oil, its attempted delivery to Syria could also be a violation of US sanctions on Iranian oil exports.

Donald Trump says US 'won't need an exit strategy' in war with Iran

Iran, a key ally of Bashar al-Assad, Syria’s president, has been placed under heavy sanctions by the US after Donald Trump pulled out of the 2015 nuclear deal.

Tehran has offered to return to the agreement, but the US president has rejected the deal, arguing it was too generous to Iran and did not address its involvement in regional conflicts.

In May, the US dispatched an aircraft carrier, bombers and fighter jets to the Persian Gulf in response to alleged Iranian threats.

The US has also accused Iran of being involved in the bombing of oil tankers in the Gulf and said it shot down an American drone in international airspace.