Fight to block AT&T, T-Mobile merger

Driven by antitrust concerns, U.S. regulators are fighting hard to block AT&T's $39 billion deal to buy Deutsche Telekom's T-Mobile USA. But smaller U.S. wireless rivals may suffer more if the deal is blocked than if it is approved.

T-Mobile USA would emerge as a stronger competitor thanks in large part to the hefty breakup fee it is entitled to under the AT&T deal.

And on its own, it is likely to fight harder for the low end of the market that is currently the playing ground for the likes of Sprint Nextel Corp., MetroPCS Communications Inc. and Leap Wireless International, analysts said.

The AT&T deal -- the largest transaction announced this year -- has run into serious obstacles both at the Department of Justice and at the Federal Communications Commission, which worry about the antitrust implications of a merger of the No. 2 and No. 4 U.S. wireless carriers.

AT&T has said it would withdraw its application to the FCC to focus on persuading the Justice Department. The company also said it would take a $4 billion charge to account for a breakup fee in case the takeover fails.

Under the terms of the merger agreement, a failed deal would entitle T-Mobile USA to $3 billion in cash plus spectrum and roaming agreements.