Comcast said Thursday it has reached an agreement to acquire Time Warner Cable in an all-stock transaction worth $45.2 billion.

Comcast Chairman and CEO Brian Roberts called the deal "pro-competitive" and "pro-consumer," and said he's confident it will be approved despite concerns about the two largest cable companies combining.

"We're going to be able to bring better products, faster Internet, more channels, On-Demand, TV Everywhere, in a national-local platform that's really special," Roberts said in a CNBC "Squawk Box" interview.

The deal was worth $158.82 per share at Wednesday's closing stock prices, a premium of just over 17% to Time Warner Cable's shares.

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Comcast shares fell while Time Warner Cable rose sharply Thursday. At the close the deal's value fell to $43.4 billion and the premium fell to 5.2 percent.



The new company would be by far the largest cable provider in the nation with more than 33 million subscribers. It is expected to face a tough review from the Federal Communications Commission.

"We want them to own more cable, and they're buying Time Warner Cable at what appears to be a very a reasonable price. I do think it gets done," Gabelli Funds portfolio manager Chris Marangi said in a CNBC interview.

Like Roberts, Time Warner Cable Chairman and CEO Robert Marcus said he felt confident the deal would clear regulatory hurdles. He added that the deal maximizes shareholder value.



Roberts said the deal will give the cable and media company a wider distribution of its products, adding that all of Comcast's competitors are national players and this deal puts it on a level playing field.

"One of the things that this transaction allows is about a $1.5 billion worth of synergies. That's mostly because we don't have any overlap in our markets and we're able to reduce some of the overhead, some of the duplication where we both have to produce guides and network operations," he said.

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