The sanctions relate to Informatics Services Corporation (ISC), the technology arm of the Central Bank of Iran (CBI), the Treasury Department said in a statement.
US media called the announcement a "bombshell" and "startling," although in reality deep divisions have driven the two men apart since leaving office, and an endorsement would have been a surprise.
The Huthis have attacked Red Sea shipping for months since the Israel-Hamas war broke out on October 7, saying they are targeting Israeli-linked vessels in solidarity with Palestinians in Gaza.
