It's time for the United States to hold Iran accountable.

Trump's tweet followed Iranian President Hassan Rouhani cautioning the American leader on Sunday about pursuing hostile policies against Tehran, saying: "War with Iran is the mother of all wars."

Trump's tweet followed Iranian President Hassan Rouhani cautioning the American leader on Sunday about pursuing hostile policies against Tehran, saying: "War with Iran is the mother of all wars."

"You are not in a position to incite the Iranian nation against Iran's security and interests," the Iranian leader said, in an apparent reference to reports of efforts by Washington to destabilize Iran's Islamic government. Still, Rouhani did not rule out peace between the two countries.

The heated exchange comes as tension between the two nations has increased since Trump pulled the U.S. out of a nuclear deal with Iran that was struck during the Obama administration.

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