(AP) – A federal appeals court on Thursday blocked a San Francisco law requiring health warnings on advertisements for soda and other sugary drinks in a victory for beverage and retail groups that sued to block the ordinance.

The law violates constitutionally protected commercial speech, the 9th U.S. Circuit Court of Appeals said in a unanimous ruling.

The judges granted a preliminary injunction that prevents the ordinance from taking effect and kicked the case back to a lower court.

The required warnings “offend plaintiffs’ First Amendment rights by chilling protected speech,” the judges wrote.

The American Beverage Association, which represents Coca-Cola, PepsiCo and others, joined retail and advertising organizations to argue in court that the rules should be blocked. The groups didn’t immediately respond to requests for comment on the ruling.

The law passed by San Francisco in 2015 required beverage advertisements within city limits to include warnings that drinking sugary drinks contribute to health problems.

The judges wrote that the city “may be commended for aiming to address serious and growing public health problems.” But they agreed that beverage companies were likely to suffer irreparable harm if the law went into effect because the warnings would drown out the ads’ main messages.

A three-judge panel of the circuit court blocked the law in 2017. The entire 11-judge panel said last year it would rehear the case.

The law is part of an effort to reduce consumption of sweet beverages as a way to combat obesity, diabetes, heart disease and tooth decay. Cities in California and across the nation have imposed taxes on sodas and other sugary drinks.

The San Francisco city attorney’s office, which argued for the law in court, didn’t immediately respond to a request for comment.