WASHINGTON — The Obama administration took another step on Friday to enforce a federal mandate for health insurance coverage of contraceptives, announcing how the new requirement would apply to the many Roman Catholic hospitals, universities and social service agencies that insure themselves.

In such cases, the administration said, female employees and students will still have access to free coverage of contraceptives.

The coverage will be provided by the companies that review and pay claims — “third-party administrators” — or by “some other independent entity,” it said.

Kathleen Sebelius, the secretary of health and human services, said the government would guarantee women access to contraceptives “while accommodating religious liberty interests.”