Timeline: U.S.-Iran relations from 1953 coup to 2020 commander killing

FILE PHOTO: A staff member removes the Iranian flag from the stage after a group picture with foreign ministers and representatives of United States, Iran, China, Russia, Britain, Germany, France and the European Union during the Iran nuclear talks at the Vienna International Center in Vienna, Austria July 14, 2015. REUTERS/Carlos Barria/File Photo

WASHINGTON (Reuters) - Iran promised harsh revenge after a U.S. air strike in Baghdad on Friday killed Qassem Soleimani, commander of Iran’s elite Quds Force and architect of its growing military influence in the Middle East.

The U.S. said the strike was aimed at disrupting an "imminent attack" that would endanger Americans in the Middle East.