Media mogul Rupert Murdoch, 84, plans to step down from the helm of 21st Century Fox, according to CNBC. He'll turn the reins over to son James, Fox co-president with Chase Carey.

The senior Murdoch will monitor the performance of his 42-year son in the capacity of executive chairman. He controls a 39.4 percent ownership stake in the TV/studio giant.

In reporting the story, CNBC cited various sources close to the Murdochs. A Fox spokesperson noted that succession planning will be a topic at an upcoming board meeting.

Lachlan Murdoch, 43, will join his father as executive chairman. He's now co-chairman of the board.

Carey will remain in the picture in an advisor role.