COLUMBIA, SC - Four of the five largest U.S. tobacco companies sued the federal government earlier this week, saying new graphic cigarette warning labels violate their free speech rights, the Associated Press reports.

Citing images of a sewn-up corpse of a smoker and pictures of a diseased lung, the companies €" R.J. Reynolds, Lorillard, Commonwealth Brands Inc., Liggett Group LLC and Santa Fe Natural Tobacco Company Inc. €" maintain the labels unfairly urge adults to abstain from a legal product, and that the new labels would cost them millions of dollars to produce.

"Never before in the United States have producers of a lawful product been required to use their own packaging and advertising to convey an emotionally charged government message urging adult consumers to shun their products," the companies wrote in the lawsuit filed in federal court in Washington.

The complaint says the warnings go beyond conveying facts that allow people to make an informed decision about whether to smoke, but rather force them to put government anti-smoking advocacy in a more prominent position than their own brands.

The FDA has refused to comment, but when announcing the new labels earlier this year, Health and Human Services Secretary Kathleen Sebelius said the labels are frank and honest warnings about smoking dangers.

The FDA approved nine new warnings that will rotate on cigarette packs. The labels must be printed on the entire top half, front and back, of the packaging, with warnings constituting 20 percent of any cigarette advertising. They also must include a phone number for a stop-smoking hotline.