(CNN) Iran has shot back at US President Donald Trump, dismissing his all-caps Twitter warning that the country would suffer consequences if it continued to threaten the US, saying it was unimpressed by the late-night tweet.

"COLOR US UNIMPRESSED," Iran's Foreign Minister Mohammad Javad Zarif tweeted Monday night, employing Trump's penchant to use all capital letters in his tweets.

"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."

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

Zarif's online comments are the latest in the escalating war of words between Washington and Tehran. Zarif's tweet comes less than a day after Trump posted a furious Twitter warning to Iranian President Hassan Rouhani.

"NEVER, EVER THREATEN THE UNITED STATES AGAIN OR YOU WILL SUFFER CONSEQUENCES THE LIKES OF WHICH FEW THROUGHOUT HISTORY HAVE EVER SUFFERED BEFORE," Trump tweeted after returning to the White House from a weekend at his golf resort in Bedminster, New Jersey.

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