Pompeo said in a statement that Hook has been my point person on Iran for over two years and he has achieved historic results.Hook will be replaced after an as-yet undetermined transition period as Iran envoy by Elliott Abrams, the U.S. envoy for Venezuela.
Hook, a longtime Republican foreign policy fixture, was an early arrival in the Trump administration.
After Tillerson was fired, Pompeo appointed Hook to the Iran position.
As policy planning chief, Hook tried to strengthen the Iran deal, which Trump denounced during the 2016 presidential campaign as the worst deal ever and pledged to pull out from.
Once he became Iran envoy, Hook was in charge of identifying sanctions to be restored and trying to lobby Europeans and others to follow suit.