Iran’s Revolutionary Guard has seized a “foreign” tanker with 12 people on board in the Strait of Hormuz, accusing the crew of smuggling oil.

A report on state television said the boat was taking fuel from Iranian smugglers to foreign customers when it was intercepted south of Iran’s Larak Island.

The vital oil shipping route has become a flashpoint in a standoff between Iran and the US, which was sparked when President Donald Trump abandoned a landmark nuclear deal and reintroduced sanctions.

Just days ago, a tanker from the United Arab Emirates disappeared from trackers in Iranian territorial waters, sparking fears that it had been seized by Iran.

Iran said it had come to the aid of a ship after receiving a distress call, but on Thursday the Revolutionary Guards said the vessel had been impounded.

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

“The vessel that Iran towed to its waters after receiving a distress call was later seized with the order from the court as we found out that it was smuggling fuel,” the guard said in a statement quoted on state television.

Images released later by Iran revealed the impounded tanker was called MT Riah – but it is still unclear who owns it.

Tensions have been high in the Strait of Hormuz since British Royal Marines seized an Iranian tanker in Gibraltar on suspicion that it was ferrying a cargo of 2.1 million barrels of crude oil to Syria, in contravention of European sanctions.

Iran’s supreme leader, Ayatollah Ali Khamenei, vowed to retaliate to the seizure, calling it an act of “piracy”.

“God willing, the Islamic Republic and its committed forces will not leave this evil without a response,” he said.

Last week, Iranian boats tried to impede a British oil tanker before being seen off by a Royal Navy frigate in the Strait of Hormuz.

In response, the Ministry of Defence announced the deployment of another Royal Navy boat and a Royal Fleet Auxiliary vessel to the Persian Gulf.