AT&T on Friday announced a new initiative to try to steal business away from T-Mobile, but T-Mobile’s outspoken CEO was unfazed. In a series of messages posted on his Twitter account and retweeted from other Twitter accounts on Friday afternoon, chief T-Mobile executive John Legere fired shots directly at AT&T and its CEO for the carrier’s attempt to buy back the business Legere claims it lost to T-Mobile. “#Randall – you gave us cash & spectrum AND we took your customers with #Uncarrier moves, do you really think you can buy them back?” Legere wrote, speaking directly to AT&T CEO Randall Stephenson and referring to the breakup fee AT&T had to pay out following its failed attempt to acquire T-Mobile in 2011.

With a new initiative unveiled on Friday, AT&T is offering customers an incentive of up to $450 per line to switch their service away from T-Mobile. The move is believed to be a preemptive strike ahead of T-Mobile’s fourth “Uncarrier” announcement, which is coming next week at CES 2014 and is believed to include an offer to reimburse contract termination feeds for customers who switch from another carrier to T-Mobile.

Legere clarified his position further in an email conversation with Re/code. “This is a desperate move by AT&T on the heels of what must have been a terrible Q4 and holiday for them,” Legere said. “Consumers won’t be fooled… nothing has changed, customers will still feel the same old pain that AT&T is famous for. Just wait until CES to hear what pain points we are eliminating next. The competition is going to be toast!”