The United States will quickly strike back, "perhaps in a disproportionate manner," if Iran strikes any American person or target, U.S. President Donald Trump said on Sunday.
"These Media Posts will serve as notification to the United States Congress that should Iran strike any U.S. person or target, the United States will quickly & fully strike back, & perhaps in a disproportionate manner. Such legal notice is not required, but is given nevertheless!" Trump said on Twitter.
American forces on Friday killed Iranian military commander Qassem Soleimani, fueling anti-American protests across Iran and ratcheting up tensions between the two longtime adversaries.
Meanwhile, the United States has detected a heightened state of alert by Iran's missile forces across the country, a U.S. official told Reuters, adding it was unclear whether the higher readiness level was defensive in nature or not.
The official, who spoke on condition of anonymity, did not provide further details or say whether the Iranian missiles were taking aim at any specific targets, amid threats by Tehran of retaliation over a U.S. drone strike last week that killed a top Iranian general.
"They're clearly at a heightened state of alert. Is that heightened state of alert to be better prepared defensively or to be better prepared offensively? That can't be determined at this point," the official said.
"But we're watching it closely."