WASHINGTON - The killing of a top Iranian general by the United States was an act of state terrorism and Iran will respond proportionately, Iranian Foreign Minister Mohammad Javad Zarif said in an interview with CNN aired on Tuesday.

"This is state terrorism," Zarif said of the killing of Qassem Soleimani in a U.S. drone attack in Baghdad last week.

"This is an act of aggression against Iran, and it amounts to an armed attack against Iran, and we will respond. But we will respond proportionately."

(Reporting by Mohammad Zargham; Editing by Andrew Heavens) ((mohammad.zargham@thomsonreuters.com;))