Donald Trump said he was not seeking a war with Iran, or "regime change," after assassinating the country's top general in an audacious drone strike.
The US president said he had acted to prevent a plot against America by General Qassim Soleimani, who he called a "sick monster"and "the number one terrorist anywhere in the world."
Mr Trump said: "We took action last night to stop a war, we did not take action to start a war.
"Soleimani made the death of innocent people his sick passion, contributing to terror plots as far away as New Delhi and London. His reign of terror is over.
"He was plotting imminent and sinister attacks on American diplomats and and personnel but we caught him in the act and terminated him."