(Bloomberg) -- The pharmaceutical industry hinted that it will fight an anticipated U.S. government proposal that would require companies to share drug prices in advertisements on free-speech grounds.

The Department of Health and Human Services plans to require drug companies to disclose the full list prices of drugs in TV ads, according to a person familiar with the matter. The agency is holding a news conference later on Monday where it is expected to announce its plans. As part of a far-reaching effort to lower drug prices, the White House has proposed that drugmakers tell consumers the list price of a drug in TV ads.

“We do have concerns about the approach of just putting list prices in ads in isolation and we believe there are substantial statutory and constitutional concerns,” said Steve Ubl, chief executive officer of the Pharmaceutical Research and Manufacturers of America, during a conference call Monday.

The group says any U.S. requirement to disclose list prices in advertising could violate the First Amendment because of restrictions on “compelled speech.” Instead, PhRMA said that companies will refer patients to websites with more information about costs in their ads. The sites, managed by drugmakers, will have list prices and other information about a medication’s cost.

“We think putting a list price in isolation in an ad itself is very confusing, misleading and lacks appropriate context,” said Ubl.

Alex Azar, the U.S. health secretary, said that the proposal was a “small step in the right direction” but that the administration planned to go further than the industry’s plans.

“Our vision for a new, more transparent drug-pricing system does not rely on voluntary action,” Azar said in a statement. “The drug industry remains resistant to providing real transparency around their prices, including the sky-high list prices that many patients pay.”

Drugmakers have long resisted disclosure of list prices to consumers, arguing that doing so could be misleading because of rebates and insurance co-pays that can change what people actually spend. Critics of the industry say list prices are relevant because many Americans have co-insurance and high-deductible plans that force them to shoulder a significant portion of a drug’s price. The industry will proceed with its plan while awaiting word of the new federal rule.

To contact the reporters on this story: Cynthia Koons in New York at ckoons@bloomberg.net;Anna Edney in Washington at aedney@bloomberg.net

To contact the editors responsible for this story: Drew Armstrong at darmstrong17@bloomberg.net, Timothy Annett

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