The companies said Lachlan Murdoch would become the sole chairman of News Corp and would continue to serve as president and chief executive of Fox. This shift reinforces Lachlan's role as leader of the media empire, putting an end to questions about succession within the Murdoch family.

In a memo to employees, Murdoch wrote: "Our companies are fine, and so am I."

The shift coincides with the proximity of the annual shareholders' meeting at Fox and News Corp in mid-November.

It also comes just months after Murdoch, 92, scrapped a plan that would have reunified his media empire by merging Fox and News Corp, after many major shareholders rejected the proposal on the grounds that it would fail to bring the company's full value.

Murdoch will be appointed honorary chairman of the two companies, which he holds almost controlling stakes in both.

Lachlan runs Murdoch's empire at a time when the media industry is facing challenges ranging from low traditional TV viewership to news organizations battling with tech companies over allegations of copyright theft in the age of artificial intelligence.

Fox News remains the number one news network in the United States and plays an influential role in American politics.