Donald Trump has said he wants to “make Iran great again” as he announced additional sanctions on Tehran.

The US president made the announcement on Sunday, as he left for his retreat at Camp David to discuss options concerning the Middle Eastern country.

Tensions in the region are high after the US accused Tehran of attacking oil tankers in the Gulf of Oman and shooting down an unmanned drone.

“We are moving forward with additional sanctions on Iran,” Mr Trump told reporters. “They’re going on slowly and in some cases pretty rapidly.”

The president stressed military action was still a possibility, after he called off a planned strike, but said he wanted the response to be “proportionate”.

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

Mr Trump said it was important to “start over on Iran” and added a riff on his regularly-repeated slogan: “Let’s make Iran great again.”

He went on to say that hopefully Tehran would be “smart” about the conflict and “cares about its people”, adding that he had a number of Iranian friends who were “high quality people”.

Mr Trump also noted that while his security adviser, John Bolton, was “definitely a hawk”, he intended to listen to every perspective on dealing with the problem.

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In an interview with NBC’s Meet the Press, the president said a war with Iran would cause “obliteration like you’ve never seen before”, but said he had no desire for armed conflict.

“I’m not looking for war, and if there is, it’ll be obliteration like you’ve never seen before. But I’m not looking to do that,” Mr Trump said.

The comment was reminiscent of his "fire and fury" rhetoric directed at North Korea, which softened once he and Kim Jong-un got to the negotiating table.

It came as Iran reportedly executed a former employee of its defence ministry on charges of spying for the CIA.

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Documents and spying equipment were found at Jalal Hajizavar’s home, IRIB News reported.

Mr Hajizavar, who had left his position as an aerospace contract employee for the ministry nine years prior, was convicted by a military court and sentenced to death.

Tensions between the US and Iran have escalated after Mr Trump pulled out of the Iran nuclear deal.