The federal government is trying to convince a skeptical judge that tobacco companies should be required to put large graphic photos on cigarette packs to show that the habit kills smokers and their babies.

Cigarette makers told U.S. District Judge Richard Leon at a hearing Wednesday that they can't be forced to spread the government's anti-smoking advocacy on the products they legally sell.

Attorneys for the Obama administration countered that the photos of dead and diseased smokers it wants on all cigarette packs are "factually uncontroverted."

Leon has already ruled that the cigarette makers are likely to succeed in their lawsuit to stop the requirement, which was supposed to go into effect next year.

Leon blocked the rule until after the lawsuit is resolved, which could take years.