NEW ORLEANS — Energy companies have reoccupied nearly 400 of the production platforms in the Gulf of Mexico that were abandoned in advance of Hurricane Isaac, a federal agency said Saturday, though offshore oil production still remains almost entirely shut down.

Oil and gas workers began retaking the offshore sites Friday and federal officials said that 377 of the 596 productions platforms have some staffing on them, up from just 97.

Yet officials estimate that 94 percent of oil production, and about 65 percent of natural gas production in the Gulf of Mexico, remains shut in in the aftermath of the hurricane.

It will take a few days for production to be fully restored, according to energy companies with operations in the gulf.

“Once onsite inspections are complete and facilities deemed safe, they will be restarted, and oil and natural gas production will be recommenced in coming days,” BP said in a news release. The company said initial aerial inspections showed no significant

damage.

The network of platforms, pipelines and storage facilities is massive, however, and exploration and production companies cannot recommence full operations until the chain of energy infrastructure is reconnected.

“Apache personnel are returning to the platforms and inspecting facilities,” Bill Mintz, spokesman for Apache Corp., said in an email. “The process of restoring production will take a number of days and will be impacted by the pace of resumption of activities by the pipelines and processing facilities operated by other companies.”