Opponents of the drilling declared victory on Thursday after the government acknowledged that permits to allow seismic blasting in the ocean — the first step toward locating oil deposits for drilling — will expire next month and not be renewed.

Nine state attorneys general and several conservation groups filed a federal lawsuit early last year to block seismic blasting, arguing it could harm endangered whales and other marine animals. The court battle dragged out so slowly that, in the meantime, time ran out on the permits.

Donna Wieting, director of the National Marine Fisheries Service, a division of the National Oceanic and Atmospheric Administration, said Thursday that her agency “has no authority to extend the terms of those [permits] upon their expiration. Further, NMFS has no basis for reissuing or renewing these [permits].” The five companies that were granted permits would have to restart the months-long process leading to approval