The Parkhead club have lined up Stromsgodset head coach Deila to replace Neil Lennon.
He guided the club to the Norwegian title, ahead of more established teams, and the manager of rival club Valerenga, Kjetil Rekdal, believes Celtic are making a shrewd appointment.
"He has been an insanely good manager," Rekdal said. "Ronny's priority is to play attractive football. He has taken them from being a dull, boring side to one who plays good football and wins titles."