Cable television provider Comcast will buy a majority stake in NBC Universal in a deal worth $US13.75 billion.
It will create a media superpower that will control not just how television shows and movies are made, but how they are delivered to the home, the BBC reports, a move that worries consumer groups.
Under the deal, General Electric's stake will fall from 80% to 49%, and all of Vivendi's 20% stake.
NBC Universal owns the NBC television network, Universal Pictures, and cable networks such as Bravo and CNBC, as well as the Universal Studios theme parks.
But critics suggest savings from a tie up will be small, and competition regulators will insist on prohibitive restrictions.