A federal judge said Monday that the Biden administration could not require masks be worn on airplanes and public transportation. The Centers for Disease Control and Prevention does not have the authority to introduce a mask mandate and did not follow the proper rules to implement a mandate, US District Judge Kathryn Kimball Mizelle wrote in the ruling.

The mask mandate has been in place since January 2021. The CDC had just last week extended it through May 3rd. It had been set to expire on April 18th, the same day the judge made the ruling.

Public transit was one of the last places masks were reliably required in the United States — most states and cities have dropped their mandates, although some have re-introduced mask-wearing rules indoors in the face of rising COVID-19 cases. The CDC said in February that masks were no longer needed on school buses.

COVID-19 cases are ticking up across the country as highly contagious versions of the Omicron variant take over as the predominant form of the virus in circulation.

The Transportation Security Administration won’t enforce mask wearing on public transportation, CNBC reports citing an unnamed administration official. The White House press secretary said the administration was still reviewing the order and the Justice Department will decide whether to appeal.