Washington — Senator Marco Rubio, a Republican from Florida, argued Sunday that the drone strike that killed Iranian military leader Qassem Soleimani "had to happen," saying President Trump had an obligation to take action when presented with what Rubio said was intelligence about an "imminent threat" to Americans.

"The Iranians at the end of the day do cost and benefit analysis, and for whatever reason they calculated that the benefits of these continued attacks, through these proxy groups, the benefits of that outweighed the costs," Rubio said on "Face the Nation." "And it was time for the president to reset that analysis for them and he did through this strike and through the strike last Friday as well. It was an important moment and it had to happen."

Soleimani, the head of Iran's secretive Quds Force, was killed in an airstrike in Baghdad early Friday, further heightening tensions between the U.S. and Tehran. The Pentagon said Mr. Trump ordered the strike.

The president said Friday that Soleimani, who he said was responsible for the deaths of hundreds of Americans, was plotting imminent attacks on U.S. diplomats and military personnel, though administration officials have declined to reveal details.

Rubio said he knew what the threat against U.S. interests was and that the president had "actionable, reliable intelligence," but said he "cannot be disclosed at this time." He stressed that Mr. Trump had an obligation to act if he had information that Americans were at risk.

"The question is, how would you justify not acting on even the possibility that Americans could die?" the Florida senator.

If Americans were killed in attacks ordered by Iran, Rubio added, "what this show would be about today is how could the president have allowed hundreds of Americans to be killed and not have done something to prevent it ahead of time."

While the president said the strike targeting the Quds leader was not intended to start a war, he warned in a series of tweets Saturday that if Iran followed through with its threat of "crushing revenge," the U.S. would hit 52 Iranian sites "very fast and very hard."