CNN chief Jim Walton quit Friday, saying the beleaguered news network needs a different leader.
"CNN needs new thinking. That starts with a new leader who brings a different perspective, different experiences and a new plan," Walton, who had been president of CNN since 2003, said in a memo to staff on Friday.
A search will begin immediately for a new president, the network said.
Walton built CNN into a profitable international news organization in his years as boss. But the U.S. flagship network has suffered through some historically poor ratings in the past few months and is entrenched in third place behind rivals Fox News Channel and MSNBC in prime time.
For the second quarter, CNN posted its weakest primetime ratings in 21 years, while its total viewers also fell 35 percent from a year earlier.
CNN historically suffers in the ratings during slow news periods, a fate Fox and MSNBC have minimized for themselves with partisan shows in prime time. Walton has resisted this approach, believing CNN's strength lies in being a nonpartisan news source.
He's 54 and has worked at CNN since 1981.
Reuters and The Associated Press contributed to this report.
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