efe-epaWashington DC

President Donald Trump publicly warned Iran on Sunday "never" to threaten the United States again and said that if Tehran wants to fight that will be the "official end" of the Iranian regime.

"If Iran wants to fight, that will be the official end of Iran. Never threaten the United States again!" said the president on his official Twitter account amid growing tension between Washington and Tehran.

Later, in an interview with American news channel Fox News, the president admitted that he did not want to fight with Iran but warned that he will not allow the country to have nuclear arms.

"I don't want to fight. But you do have situations like Iran, you can't let them have nuclear weapons - you just can't let that happen," he said.

"With all of everything that's going on, and I'm not one that believes - you know, I'm not somebody that wants to go into war, because war hurts economies, war kills people most importantly - by far most importantly," he added.

The president also defended his decision to withdraw the US from the 2015 nuclear agreement with Iran, which was accompanied by the resumption of sanctions that had been lifted under the pact, but admitted he "had no idea it was going to be as strong as it was."

"It totally - the country is devastated from the standpoint of the economy," he said.

Trump issued his threat a few hours after the commander of Iran's Revolutionary Guards, Hossein Salami, said on Sunday that Iran does not fear a war but the US does.

Salami said in a speech at a military ceremony broadcast on state-run Iranian TV that Tehran was not seeking war but did not fear it either, in contrast to the US, which is afraid of war and does not have the willpower to engage in one.

Salami also warned that the entire Middle East could become "a powder keg" for Washington.

Last week, the US decided to deploy to the Persian Gulf the amphibious assault ship USS Arlington, Patriot missiles, the aircraft carrier USS Abraham Lincoln and assorted warplanes, including bombers, after claiming that it had detected unspecified "indications" of Iranian plans to attack US forces in the Middle East.

In recent weeks, concern has been increasing that National Security Adviser John Bolton, a long-time hawk on Iran who was instrumental in instigating the invasion of Iraq under George W. Bush, might be working to edge the administration closer to some kind of military action against Tehran.

Last year, prior to bringing Bolton into the administration as one of his top advisers, Trump withdrew the US from the Iran nuclear deal. More recently, Trump has tightened economic sanctions against Tehran and his administration says it has increased the US military presence in the region.

It was not clear what Trump meant by his tweet on Sunday, however, since it ran counter to reports from late last week that he had told US military commanders he did not want to go to war and, in fact, wanted to reduce bilateral tensions.

On the Iranian side, Foreign Minister Mohammad Javad Zarif told Iran's IRNA news agency in Beijing, where he was on an official visit, that "There will be no war because neither do we want a war, nor has anyone the idea or illusion it can confront Iran in the region."

"The fact is that Trump has officially said and reiterated again that he does not want a war, but people around him are pushing for war on the pretext that they want to make America stronger against Iran," Zarif said.

For the moment, neither the Pentagon nor the State Department has provided proof to the media of the alleged Iranian plans to attack US forces, a situation which has generated skepticism among Democratic lawmakers as well as among several key US allies.

The Washington Post reported last week that Trump has been frustrated with some of his top advisers because he thinks that the US is taking too belligerent a stance vis-a-vis Tehran, and The New York Times said that the president had told Pentagon chief Patrick Shanahan that he does not want a war with Iran.