CNET

Once upon a time, AT&T wanted to own T-Mobile. Now it wants to destroy its competitor.

AT&T will offer T-Mobile customers up to $450 per line to switch their service to its network, the company announced Friday. It will give customers $200 credit for every line they transfer from T-Mobile. That credit will be available only to those customers who switch and choose an AT&T Next plan and either activate a phone or buy a new one at full retail price.

In addition, AT&T said that it'll give customers a promotion card of up to $250 for every smartphone trade-in they bring to the table. The actual promotion card amount is based on the type of device, its age, and quality. AT&T didn't say what devices might reach the $250 mark. The company also pointed out that its promotion cards can only be used "toward purchases of eligible AT&T products & services or to pay your wireless bill."

AT&T's move reflects an increasingly believable rumor suggesting that T-Mobile will announce at the Consumer Electronics Show (CES) next week that it will offer a similar offer for AT&T customers looking to switch to its network. T-Mobile might also offer the switch deal for other carriers, as well.

That AT&T has fired a pre-emptive shot at T-Mobile could perhaps say something about the pressure it's feeling from its smaller competitor. However, in an e-mailed statement to CNET, AT&T representative said that the new deal is simply a standard maneuver in an already competitive industry.

"Wireless has always been a very competitive industry and a move like this should not be unexpected," the representative said. "As you know, there are handset promotions all the time."

The AT&T rep went on to tell CNET that "while this promotion is targeted to T-Mobile customers, Sprint and Verizon customers can get a minimum $100 trade-in when they choose Next, plus pay only $25 per smartphone on Mobile Share Value plans."

Still, AT&T's hard line regarding T-Mobile says a lot. It's arguably easier for smartphone users to switch between those two carriers than with Sprint or Verizon because their networks run on the same technology. T-Mobile has also clearly made it a priority to challenge its competitors. This week, in fact, T-Mobile CEO John Legere posted an image of his company's resolutions for 2014. His last item said to "give AT&T a break...or not."

That the two carriers are at such odds today stands in stark contrast to their position not so very long ago when AT&T announced plans to acquire T-Mobile USA for $39 billion. After months of intense lobbying and suffering through critics' complaints, AT&T abandoned its bid to acquire T-Mobile at the end of 2011. The breakup forced AT&T to pay T-Mobile $3 billion in cash for its trouble.

CNET has contacted T-Mobile for comment on the AT&T move. We will update this story when we have more information.