BE CAUTIOUS!,” Mohammad Javad Zarif posted a message on his Twitter page on Monday, in reaction to US President Donald Trump's baseless allegations and threats against Iran.

Iranian Foreign Minister Mohammad Javad Zarif in a tweeted message reminded the US that the Iranian nation has seen fall of empires.

“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".

The Iranian president on Sunday, addressing a meeting attended by Iranian representatives in foreign countries, said that the US last resort is aimed at exhausting the Iranian people.

'The Iranian people are the master and they will never bow to anyone,' President Rouhani said.

He said that the Americans should come to realize that establishing peace with Iran is the mother of all peace and waging war with the country is mother of all wars.

US president Donald Trump responded angrily to Iranian counterpart Hassan Rouhani's suggestion that the US is "playing with the lion's tail", warning of severe “consequences,” as rhetoric between the two countries' escalated.

In a direct, all-caps threat on Twitter Trump said: "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,"

The comments came at the same time as US secretary of state Mike Pompeo was speaking about the Trump administration "diplomatic and economic pressure campaign against Iran at Reagan Forum in Simi Valley, California.

Pompeo said that the U.S. government was launching a 24/7 Farsi-language channel on TV, radio, digital and social media formats to reach Iranians in Iran and around the globe.

In May, Trump called the nuclear accord - or Joint Comprehensive Plan of Action (JCPOA) as it is formally known - a "horrible, one-sided deal that should have never, ever been made" and withdraw from the deal.

Washington is now re-imposing the sanctions, despite objections from the UK, France, China, Russia and Germany, who all signed the 2015 agreement.

US initially planned to totally shut Iran out of global oil markets after Trump abandoned the deal, demanding all other countries to stop buying its crude by November.

But it has somewhat eased its stance since, saying that it may grant sanction waivers to some allies that are particularly reliant on Iranian supplies.