A federal judge says he’ll need at least another month to decide whether to grant his required approval of SBC Communications Inc.’s purchase of AT&T Corp. and Verizon Communications Inc.’s purchase of MCI Inc.

U.S. District Court Judge Emmet Sullivan Tuesday sent lawyers from the Department of Justice back to headquarters to collect and present to him their internal documents justifying consent decrees the agency reached with the companies allowing the mergers to win DOJ approval in January. The Justice Department found that the SBC-AT&T (now AT&T Inc.) and Verizon-MCI mergers were anti-competitive and imposed narrowly crafted divestitures to remedy those harms.