The FCC could override the OMB's decision, but a ruling by the appeals court might still block it.

The CTIA has argued the regulation would be onerous and unnecessary.

"CTIA is pleased the Office of Management and Budget recognized that the FCC failed to seek and evaluate public comment on these important rules at the inception of the rulemaking process," the industry group said in a statement Tuesday. "Having the flexibility to adapt to unique emergency situations will better serve American wireless consumers. Carriers already have implemented flexible business continuity/disaster recovery plans that address their backup power needs and enhance network reliability and resiliency."

AT&T, BellSouth and other carriers earlier had argued against requiring specific provisions for keeping service available after disasters. Mobile operators deployed portable base stations on trucks to restore service in some areas after Katrina.