Comcast CEO Brian Roberts Chip Somodevilla / Getty Images Comcast is set to buy Time Warner Cable in an all-stock deal that values Time Warner at $159 per share, CNBC's David Faber reports on Twitter.

At $159, Comcast would be paying an 18% premium to today's closing price. It would value Time Warner Cable at ~$45 billion. Comcast is valued at $146.5 billion.

This would make one gigantic cable company.

Comcast is the biggest cable provider in the U.S. with 23 million subscribers. Time Warner is the second biggest with 12 million subscribers. The next closest is Cox with 4.6 million subs. (All numbers from Wikipedia.) Satellite company DirecTV has 20 million subscribers.

Time Warner Cable has been in play for months now. Charter has been trying to merge with Time Warner Cable. It even nominated a full slate of board members.

But Charter was only offering $132.50 per share for Time Warner, which Time Warner rejected as "grossly inadequate," according to The New York Times.

Time Warner was holding out for a better deal, and it looks like it got one.

However, this is far from a done deal. It will come under heavy government scrutiny.

This would create the biggest pay-TV business by a mile. There's not exactly a ton of competition in the world of cable, but this would effectively make it nonexistent.

Here are the tweets:

Comcast to buy Time Warner Cable in all stock deal worth $159 per $TWC share- sources. Deal set for tomorrow morning. Ratio is 2.875 $CMCSA. — DAVID FABER (@davidfaber) February 13, 2014

Comcast will indicate willingness to divest 3m subs from combination with $TWC- sources. — DAVID FABER (@davidfaber) February 13, 2014