Washington: In his sternest direct threat to Tehran, US President Donald Trump has warned that a military confrontation with America would "be the official end of Iran."
Tensions between the US and Iran have been growing as the Trump administration has deployed a carrier strike group and B-52 bombers to the Gulf, citing Iranian "threats."
"If Iran wants to fight, that will be the official end of Iran," he said in a tweet on Sunday. "Never threaten the United States again!"
The terse tweet comes amid rising fears over a potential military confrontation between the two countries. Trump administration officials are debating recent intelligence regarding whether Iran or the militias it supports are possibly planning to attack US assets in the Gulf or whether it is acting defensively in an attempt to deter US action.
Trump's tweet marks a shift in tone after recent attempts from both sides to downplay the possibility of dangerous military conflict.
In an interview with Fox News broadcast on Sunday, Trump vowed that he would not let Iran develop nuclear weapons but said he did not want a conflict.
"I'm not somebody that wants to go into war, because war hurts economies, war kills people most importantly - by far most importantly," the US president said.
Reacting to Trump stepping up his rhetoric toward Tehran, the country's foreign minister Mohammad Javad Zarif said Monday the US President's "genocidal taunts" will not "end Iran".
"Iranians have stood tall for millennia while aggressors all gone. Economic terrorism and genocidal taunts won't 'end Iran'," Zarif tweeted.
"Never threaten an Iranian. Try respect -- it works!" he said.
The latest Washington-Tehran frictions come after Iran suspended its commitments under the 2015 landmark international nuclear deal, and threatened to resume production of enriched uranium which is used to make reactor fuel and nuclear weapons.
The deal aimed to cut sanctions on Iran in exchange for an end to its nuclear programme, but the US unilaterally withdrew from the agreement last year.
Calling the deal "defective", Trump then re-imposed crippling sanctions on Iran.
The Trump administration has attempted to use a combination of hawkish rhetoric, diplomatic pressure, economic sanctions and now military posturing in order to fundamentally change the nature of the Iranian regime, CNN reported.
US Secretary of State Mike Pompeo said in a speech last year that Washington's actions, including abandoning the nuclear deal with Tehran, were meant to force Iran to behave like a "normal" country -- one that doesn't sponsor terrorism or seek to develop nuclear weapons. But many saw the address as a call for the regime in everything but name.
Pompeo said last week that the Trump administration doesn't want war with Iran but warned of a "swift and decisive" response from the US, should Iran initiate an attack.
"The regime in Tehran should understand that any attacks by them or their proxies of any identity against US interests or citizens will be answered with a swift and decisive US response," he said.
Earlier this month, US national security adviser John Bolton said the US deployed the USS Abraham Lincoln Carrier Strike Group and a bomber task force to the Middle East in response to a "number of troubling and escalatory indications and warnings" from Iran.
"The United States is not seeking war with the Iranian regime," Bolton wrote in a statement released by the White House, "But we are fully prepared to respond to any attack, whether by proxy, the Islamic Revolutionary Guard Corps, or regular Iranian forces."
Iran has also moved to talk down concerns over the escalating tensions. On Saturday, its foreign minister Zarif insisted there was no appetite for war.
"There will not be a war since neither we want war nor does anyone have the illusion they can confront Iran in the region," Zarif said.