The role has been vacant since Malcolm Green and Gary Betts, the executive creative directors and founding partners of DLKW, left last April after the agency completed its three-year earn-out deal with Creston.
Since Green and Betts' departure, the DLKW chairman, Greg Delaney, has taken over running the creative department. Prest will report to him.
Prest's exit from Lowe follows that of Ed Morris, the executive creative director.
Both Morris and Prest joined Lowe London from Bartle Bogle Hegarty in 2005. Prest began his career at Bartle Bogle Hegarty as a junior copywriter in 1999. He joined Lowe London as a senior copywriter and became a creative director in 2007.
Last year, he won awards for the John Lewis campaign "shadows". In the past, he has picked up accolades for campaigns including Stella Artois' "le sacrifice", Levi's' "anti-fit" and Sure's "no white marks".
Delaney said: "George is smart and experienced. He is a thoroughly modern creative in believing digital solutions are every bit as important as TV and print work."