President Trump warned Iran late Monday that the U.S. would respond with military action if the country launched an attack to avenge the killing of top Iranian Gen. Qasem Soleimani in an American airstrike in Iraq.

What he's saying: "Any attack by Iran, in any form, against the United States will be met with an attack on Iran that will be 1,000 times greater in magnitude!" Trump tweeted, noting press reports that Iran may be planning a retaliatory assassination, "or other attack, against the United States."

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