Afederal judge on Monday struck down the Centers for Disease Control and Prevention's rule that required all travelers to wear masks on airplanes, buses, trains and other modes of public transportation, with the White House later saying that the "decision means CDC’s public transportation masking order is not in effect at this time.”

The ruling, which called the mandate "unlawful," said the CDC had overstepped its legal authority by imposing the mandate in February 2021.

The mask requirement "violates the procedures required for agency rulemaking," U.S. District Court Judge Kathryn Kimball Mizelle wrote.

The CDC had renewed the travel mask mandate several times, most recently extending it through May 3.

Because of Monday's ruling, a Biden administration official said, "TSA will not enforce its Security Directives and Emergency Amendment requiring mask use on public transportation and transportation hubs at this time."

Airlines for America, a trade association representing major North American airlines, seemed to welcome the ruling, but couldn't speak for its individual members.

"U.S. airlines have been strong advocates for eliminating pandemic-era policies and are encouraged by the lifting of the federal transportation mask mandate," the group said.

Several airlines, including United and Alaska, issued statements saying masks are now optional.