Pompeo promised United States aid to Iranians who would rise up against their government officials, whom he said were "merely polished front men for the ayatollahs' global con artistry".
"Iran is not the same country anymore, that I can say", Mr Trump said while addressing the VFW National Convention in Kansas City, Missouri.More news: Avenatti says Cohen has more Trump tapes
Two weeks ahead of re-imposing sanctions against Iran, the Trump administration is stepping up the pressure on the Islamic republic.
Trump's threat to Iran came hours after a speech by U.S. Secretary of State Mike Pompeo who denounced Iran's clerical leadership as a "mafia" and promised unspecified backing for Iranians unhappy with their government.
Gen. Gholam Hossein Gheibparvar, the chief of the paramilitary Revolutionary Guard's volunteer Basij force, said Trump "won't dare" take any military action against Iran.
Trump has made ending Iran's nuclear program a priority, saying the nuclear deal reached by former President Barack Obama only made the situation worse.
Iranian officials have said U.S. measures equal an "economic war" on Iran.More news: Adam Schiff, top intel Democrat, says Trump 'acts like he's compromised'
Recent anti-Iran tirades by the USA angered a number of Iranian officials.
He also reiterated that the administration seeks to force Iranian crude exports "as close to zero as possible by November 4", when the U.S. sanctions lifted by the nuclear deal snap back into place.
Pompeo said the Iranian economy is "going great", but only for the elite, accusing the ayatollahs and senior leaders of lining their pockets to the tune of billions of dollars while a third of Iranians live in poverty.
While Trump isn't a position to get re-elected until 2020, the president's idea of stoking Iran for a boost in poll numbers could certainly be on his mind.More news: Meghan Markle 'lives in fear' father will leak conversations
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