A federal judge in Florida on Monday declared the Biden administration's mask mandate for public transportation unlawful.

U.S. District Judge Kathryn Kimball Mizelle, who was appointed by former President Donald Trump, ruled that the U.S. Centers for Disease Control and Prevention exceeded its statutory authority by imposing masking requirements on airplanes, airports, and other forms of public transportation and transportation hubs. Mizelle wrote in a 59-page opinion that the agency did not follow proper procedure in issuing the masking order and failed to adequately explain its decisions.

"Because 'our system does not permit agencies to act unlawfully even in pursuit of desirable ends,' the Court declares unlawful and vacates the Mask Mandate," the judge wrote.

The decision comes just days after the CDC extended the mask mandate for an additional two weeks, citing concerns over rising coronavirus cases cased by the BA.2 Omicron subvariant of the virus. The mandate is now set to expire May 3.

When the CDC extended the mask mandate for the fifth time last week, the agency said that the BA.2 subvariant is now the dominant coronavirus strain circulating in the U.S.

"Since early April, there have been increases in the 7-day moving average of cases in the U.S. The CDC Mask Order remains in effect while CDC assesses the potential impact of the rise of cases on severe disease, including hospitalizations and deaths, and healthcare system capacity," the agency said in a news release.

The CDC and the Transportation Security Administration put masking requirements in place in January 2021, in response to an executive order from newly inaugurated President Joe Biden. Before Biden's order, U.S. airlines and other forms of public transportation had voluntarily adopted masking rules in accordance with COVID-19 pandemic guidance from the CDC.

In recent months, the masking requirements for public transportation have become controversial as pandemic case numbers have fallen and many COVID-19 restrictions on other industries have been lifted. The CDC adjusted its masking guidance in February to permit about 70% of Americans to forgo face masks indoors because they lived in areas where the threat from the virus was low or moderate. As of March, all statewide mask mandates in the country have been lifted, with Hawaii being the last state to do so.

CDC officials have received widespread criticism for permitting indoor workplaces, restaurants, entertainment venues, and other places where large number of people gather to drop masking requirements while keeping restrictions in place for public transportation like airplanes.

The lawsuit to end the mask mandate was brought by the Health Freedom Defense Fund and two other individuals.