A US federal judge on Monday struck down the Covid-19 mask mandate for public transportation imposed by the administration of President Joe Biden, prompting major airlines to quickly drop the requirement.

US District Judge Kathryn Kimball Mizelle of the Middle District of Florida, a Trump-appointed judge, said the mask mandate exceeds the statutory authority of the Centers for Disease Control and Prevention (CDC).

The mandate requiring face masks on airplanes, subways, trains, buses, taxis and other forms of public transportation was recently extended by the CDC until May 3 amid a rise in coronavirus cases.

US airlines and a number of Republican lawmakers have called for an end to the mask mandate, which was issued by the CDC on February 3, 2021, shortly after Biden took office.

In light of the decision, the Transportation Security Administration (TSA), which runs security at airports, will not enforce directives “requiring mask use on public transportation and transportation hubs at this time,” an administration official said.

After the ruling was announced, United Airlines dropped its mask mandate on domestic flights and some international flights, depending on the rules in the country of arrival.

“While this means that our employees are no longer required to wear a mask – and no longer have to enforce a mask requirement for most of the flying public – they will be able to wear masks if they choose to do so, as the CDC continues to strongly recommend wearing a mask on public transit,” the airline said in a statement.

It was soon followed by American Airlines, Delta Airlines and Alaska Airlines, who all made masks optional for crew members and customers on domestic and most international flights.

Like United, they cautioned that travelers would still be subject to local mask regulations at their destinations.