An Iranian special forces commander has warned President Donald Trump if the US attacks Iran it "will destroy all that you possess".
Major General Qassem Soleimani vowed that if Mr Trump started a war, the Islamic Republic would end it, Iranian news agency Tasnim reported.
It follows Mr Trump's all-caps-lock tweet warning Iran's president to "never, ever" threaten the US.
Tensions have risen since the US withdrew from the 2015 Iran deal.
Maj Gen Soleimani - who leads the Quds Force of Iran's elite Revolutionary Guards - was quoted on Thursday as saying: "As a soldier, it is my duty to respond to your threats.
Angry Trump Iran threat becomes meme
"Talk to me, not to the president [Hassan Rouhani]. It is not in our president's dignity to respond to you.
"We are near you, where you can't even imagine. Come. We are ready.
"If you begin the war, we will end the war. You know that this war will destroy all that you possess."
He also accused the US president of using the language of "night clubs and gambling halls".
On Sunday, Mr Trump tweeted a startling threat to Iran's president.
To Iranian President Rouhani: NEVER, EVER THREATEN THE UNITED STATES AGAIN OR YOU WILL SUFFER CONSEQUENCES THE LIKES OF WHICH FEW THROUGHOUT HISTORY HAVE EVER SUFFERED BEFORE. WE ARE NO LONGER A COUNTRY THAT WILL STAND FOR YOUR DEMENTED WORDS OF VIOLENCE & DEATH. BE CAUTIOUS!
— Donald J. Trump (@realDonaldTrump) July 23, 2018
COLOR US UNIMPRESSED: The world heard even harsher bluster a few months ago. And Iranians have heard them —albeit more civilized ones—for 40 yrs. We’ve been around for millennia & seen fall of empires, incl our own, which lasted more than the life of some countries. BE CAUTIOUS!
— Javad Zarif (@JZarif) July 23, 2018
But two days later, while speaking to a veterans' group, the president said the US was "ready to make a real deal" with Iran.
Three reasons behind Trump ditching Iran deal
Mr Trump's angry tweet was a response to a warning by Mr Rouhani to the US.
"America should know that peace with Iran is the mother of all peace, and war with Iran is the mother of all wars," he said earlier, according to Iran's state news agency Irna.
In May, Mr Trump announced that the US was withdrawing from the Obama-era nuclear agreement with Iran, going against advice from European allies.
Mr Trump had said the Iran deal was "defective to its core".
In response, Iran had said it was preparing to restart uranium enrichment, key for making both nuclear energy and weapons.
Washington is now re-imposing sanctions on Iran's oil, aircraft exports, and precious metals trade among other sectors, despite objections from the UK, France, China, Russia and Germany, who all signed the 2015 agreementManchester United will battle fellow Premier League clubs for Yerry Mina's signature this summer
- The Colombia defender failed to impress the Catalan club in his first year at the Camp Nou
- Newly promoted side Wolves and French League side Lyon are also monitoring the player's situation
Premier League giants Manchester United are reportedly interested in signing Barcelona star Yerry Mina this summer.
The defender was impressive for Colombia at the 2018 FIFA World Cup in Russia - scoring three goals in the process.
However, he was unable to convince Barca boss in his first season at the Camp Nou as he has been tipped with a move away from the club.
READ ALSO: Test your knowledge with these World Cup quiz
According SunSport, Jose Mourinho wants a defender and has urged Ed Woodward to step up the club's £60 million pursuit of Leicester's Harry Maguire.
RMC also revealed that United are already monitoring the situation of the Barcelona star Mina, who could be available for half the price.
Everton, Wolves and Lyon are also said to be interested in signing the 23-year-old but will have to present a good bid before they can lure the player away from his club.
The Sun reveals that Mina's agent Jair Mina will be meeting with Barca chiefs to settle the future of his client.
Barcelona signed him £10 million from Brazilian side Palmeiras in January, but they know they could treble their money six months on.
PAY ATTENTION: Become a member of the leading sports Facebook group 'Naija Football Fan Zone'
The Colombia is behind first-choice centre-back pairing Gerard Pique and Samuel Umtiti but with the arrival of Clement Lenglet from Sevilla, his future may be unsure.
Everton are planning to sign both Mina and Lucas Digne from Barca as they hope to fortify their team.
Newly promoted side, Wolverhampton Wanderers have also made an enquiry about the player.
Mina looks ready-made for the Premier League with pace, strength and an ability to read the game.
But it's his aerial dominance that really stands out and the six-foot-four defender headed in three goals - including one against England - for his nation at Russia 2018.
NAIJ.com previously reported that Premier League side, Liverpool are plotting a deal for Colombia defender Yerry Mina, reports suggest.
According to UK Mirror, citing sources at Fotomac, eggheads of the Anfield outfit are satisfied with Mina's overall performance at the ongoing FIFA World Cup in Russia and are set to struggle it out with Turkish side, Fenerbahce this summer.
Mina netted three goals in as many appearances for Colombia at the Mundial, including the all-important dying minute equalizer in round of 16 painful defeat to England’s Three Lions.
But there are other flashpoints too. The US is deeply suspicious of Iranian activity in the Middle East and is aligned with Israel and Saudi Arabia, two of Iran's foes.
Iran has insisted that its nuclear programme is entirely peaceful and its compliance with the 2015 deal has been verified by the International Atomic Energy Agency.