Comcast, the media conglomerate that owns NBC News, announced a plan to spin off most of its cable television networks into a separate publicly traded company.

Comcast would retain NBCUniversal's NBC broadcast television network, its film and television studios and its theme parks, as well as its Peacock streaming service.

Comcast is planning to announce the spinoff of its cable networks, including CNBC, MSNBC and E!, on Wednesday, according to a source familiar with the matter.