WASHINGTON — The nation’s Roman Catholic bishops on Thursday rejected the latest White House proposal on health insurance coverage of contraceptives, saying it did not offer enough safeguards for religious hospitals, colleges and charities that objected to providing such coverage for their employees.

The bishops said they would continue fighting the federal mandate in court.

The administration said the proposal, issued last Friday, would guarantee free employee coverage of birth control “while respecting religious concerns” of organizations that objected to paying or providing for it.

The bishops said the proposal seemed to address part of their concern about the definition of religious employers who could be exempted from the requirement to offer contraceptive coverage at no charge to employees. But they said it did not go far enough and failed to answer many questions, like who would pay for birth control coverage provided to employees of certain nonprofit religious organizations.

“The administration’s proposal maintains its inaccurate distinction among religious ministries,” said Cardinal Timothy M. Dolan of New York, the president of the United States Conference of Catholic Bishops. “It appears to offer second-class status to our first-class institutions in Catholic health care, Catholic education and Catholic charities. The Department of Health and Human Services offers what it calls an ‘accommodation,’ rather than accepting the fact that these ministries are integral to our church and worthy of the same exemption as our Catholic churches.”