Australia’s parliament moved forward Thursday on a landmark scheme to remove trademarks and advertising from cigarette packages, defying threats of a multi-billion-dollar legal challenge from tobacco companies.

The upper house approved the bill and sent it back to the lower chamber for routine approval of several minor amendments. The law, which mandates that cigarettes be sold in plain brown wrappers bearing only brand names and health warnings, is to take effect at the end of next year.

Tobacco companies claim the law is unconstitutional and say they expect to collect billions of dollars in damages when they sue. But Health Minister Nicola Roxon said Thursday the government is ready for that fight.

Other countries require health warnings on cigarette packages, including graphic photographs of diseased lungs and gums. But the Australian legislation is believed to be the first to ban the use of promotional materials on the packages.

The tobacco companies say the law would unjustly diminish the value of their brands and trademarks in violation of the Australian constitution.

The government says it seeks to reduce the nation’s 15,000 annual smoking-related deaths.