Comcast and Time Warner Cable confirmed on Friday they had abandoned their proposed $45 billion merger.
Comcast said the deal had been structured in a way that if the US government didn’t agree, the companies could walk away.
"Today, we move on," Comcast chief executive Brian Roberts said in a statement.
The deal had faced vocal criticism from some politicians, media company executives and diverse consumer and industry groups, who had worried it would create a monolith with too much control over what Americans do online and watch on TV.
Comcast shares were up 1.2 per cent at $59.94 in premarket trading, while Time Warner Cable shares were down 0.5 per cent at $148.