DirecTV notified EchoStar Corp. of its intention to terminate an acquisition of Dish Network Corp. after bondholders failed to consent to a key debt exchange, all but killing a deal to create the largest US pay-TV service.

DirecTV had forecast that the combination could generate cost synergies of at least $1 billion per year. The deal was seen as more likely to get regulatory approval amid the rise of streaming services and the decline of pay-TV subscribers due to cord-cutting.