WASHINGTON (AP) — The Biden administration late Thursday asked the Supreme Court to block lower court orders that are keeping President Joe Biden's vaccine mandate for health care workers from going into effect in about half of the states.

The administration asked the justices to allow the "urgently needed health and safety measure to take effect before the winter spike in COVID-19 cases worsens further."

It said the requirement "will save hundreds or even thousands of lives each month."

The administration's request comes a day after the New Orleans-based 5th U.S. Circuit Court of Appeals lifted a nationwide ban on the mandate. The court instead allowed the mandate to remain blocked in 14 states that had collectively sued in federal court in Louisiana. That action altered a Nov. 30 ruling by U.S. District Judge Terry Doughty, who originally applied his order nationwide.

A different appeals court, the St. Louis-based 8th U.S. Circuit Court of Appeals, has declined to disturb a lower court order blocking the mandate in 10 other states.

The Biden administration asked the justices to allow the mandate to take effect in the 24 states covered by those two courts' decisions. A federal judge in Texas granted an injunction Wednesday that applies only to that state.

One other appeals court, the 11th U.S. Circuit Court of Appeals, allowed the mandate to remain in place, saying Secretary of Health and Human Services Xavier Becerra has the authority to require the vaccines.

At issue before the Supreme Court is a rule published Nov. 5 by the Centers for Medicare & Medicaid that applies to a wide range of health care providers that receive federal Medicare or Medicaid funding. It required their workers to receive the first dose of a COVID-19 vaccine by Dec. 6 and be fully vaccinated by Jan. 4. It was projected to affect more than 17 million workers in about 76,000 health care facilities as well as home health care providers. The mandate has religious and medical exemptions.

Legal challenges to Biden's vaccine mandate for private employers are also ongoing.

The high court in other cases has allowed vaccine mandates that are more stringent. The justices on Monday refused to halt a COVID-19 vaccine requirement for health care workers in New York that does not offer an exemption for religious reasons. And previously the court rejected an emergency appeal from health care workers in Maine to block a vaccine mandate that doesn't have a religious exemption. In both cases, three conservative justices — Neil Gorsuch, Clarence Thomas and Samuel Alito — dissented.