Now that FCC Chairman Julius Genachowski has called for an administrative hearing on AT&T's proposed buyout of T-Mobile, the two parties have decided to formally withdraw their application to the Commission. The confirmation came today, with an announcement from AT&T and Deutsche Telekom, which owns T-Mobile USA. In a statement, the two companies reiterated their commitment to the deal, adding that they're looking to receive final approval from the DoJ: "This formal step today is being undertaken by both companies to consolidate their strength and to focus their continuing efforts on obtaining antitrust clearance for the transaction from the Department of Justice." AT&T also reaffirmed that it would incur a $4 billion hit should the deal fall through, and that it expects to take out a pretax charge for that amount during the fourth quarter of this year. Of course, Genachowski's decision must still obtain approval from the full Commission, but it certainly looks like both parties are gearing up for a courtroom battle.