(AP) — A federal judge has blocked President Joe Biden's administration from enforcing a coronavirus vaccine mandate on health care workers in 10 states that had brought the first legal challenge against the requirement.

The preliminary injunction issued Monday applies to Alaska, Arkansas, Iowa, Kansas, Missouri, Nebraska, New Hampshire, North Dakota, South Dakota and Wyoming. Those states all have either a Republican attorney general or governor.

A federal judge in Missouri said the Centers for Medicare & Medicaid had no clear authority from Congress to enact the vaccine mandate for health care providers that participate in the two government programs.

The rule requires workers to receive their first dose by Dec. 6 and their second by Jan. 4.