WASHINGTON  The Obama administration has asked a federal court in Louisiana to reinstate the ban on deepwater drilling in the Gulf of Mexico, saying the moratorium was a rational response to the unparalleled emergency of the BP oil spill.

In a court filing late Tuesday, the Interior Department said that the six-month ban on drilling in more than 500 feet of water, imposed in late May, was necessary to allow time to adopt stricter safety and environmental regulation of deepwater wells.

The action has put hundreds of people who operate and service deepwater wells out of work and has brought long-term uncertainty to the Gulf Coast economy. Politicians all along the coast have called the moratorium a case of federal overkill that threatens the livelihood of the region.

The moratorium was challenged in court by Hornbeck Offshore Services, a Louisiana firm that provides goods and services to offshore drilling and pumping platforms, and by other oil service firms. Judge Martin L. C. Feldman of the United States District Court in New Orleans agreed with the company, and on June 22 issued an order blocking enforcement of the moratorium. He said the Obama administration had failed to justify the need for “a blanket, generic, indeed punitive, moratorium” on deepwater oil and gas drilling.