In a White House web video, the president says some tobacco companies are fighting new cigarette warning labels because they don't want to be honest about the consequences. Several tobacco firms have sued to block graphic new Food and Drug Administration labels for cigarette packs.
The Obama video observes Thursday's 36th "Great American Smokeout" by the American Cancer Society.
Obama says the country has made progress in reducing the number of Americans who smoke but notes that 46 million are still addicted.
Obama has fought his own smoking habit by chewing nicotine gum. His last medical report, issued Oct. 31, declared him tobacco-free.
He concedes quitting smoking is hard and adds, "Believe me, I know."