Charter Communications, one of the largest telecommunications companies in the United States, announced a merger Friday with privately held Cox Communications in a multi-billion-dollar deal. Once the merger is completed,

Charter Communications has agreed to buy privately held rival Cox Communications for $21.9 billion, uniting two of the largest cable and broadband operators in the United States as they battle streaming giants and mobile carriers for customers.

Charter agreed to acquire privately held Cox in a deal valued at $34.5 billion as cable companies confront multiple challenges.