The new policy was in keeping with New York City’s vaccine rule, which Mayor Bill de Blasio announced in early December and which is more stringent than a contested Biden administration rule requiring vaccine mandates or weekly testing at larger employers.

The New York City mandate, which requires on-site workers at all businesses to be vaccinated, is the country’s most sweeping local vaccine mandate and affects some 184,000 businesses.

“Our policy reflects the guidelines of the mandate,” a spokesman for Fox Corporation said in an email on Monday. More than 90 percent of Fox’s employees are vaccinated, the company said.