US vows 'economic D-Day' as Iran threatens to halt all oil exports

By Yasmine Ghania and Kanishka Singh CAIRO/WASHINGTON, Aug 24 (Reuters) - The U.S. threatened Iran with what it called "the greatest financial offensive ever marshalled" as it prepared to roll out economic sanctions on Monday that target Iran's trade partners. Iran in turn vowed to shut down all oil exports from the Gulf "if the economic war continues."