“Steve worked tirelessly to try and bring success to Newcastle United. He has the utmost respect of all the players, staff and management and he leaves with our very best wishes and sincere thanks.
“We feel that a change is now needed in order to give the Club the best possible chance of securing its Premier League future.
“A further announcement on a successor to Steve will be made in due course.”
Benitez will have talks with Charnley and his first match could be against Premier League leaders Leicester on Monday.