The International Trade Commission has ordered U.S. customs officials to bar imports of counterfeit cigarettes bearing the trademarks of Philip Morris USA, the nation’s No. 1 tobacco company said Thursday.

Philip Morris, owned by Richmond, Va.-based Altria Group Inc., said in a statement that the order will help stop Internet-based vendors from illegally importing cigarettes made abroad without trademark owners’ permission and selling them in the United States. The company estimates more than 800 million cigarettes were sold to U.S. consumers by Internet sellers in 2008.

In March 2008, Philip Morris USA filed a complaint with the commission as part of an effort to end the trade of counterfeit, stolen and untaxed or under-taxed cigarettes. The company said Internet-based cigarette vendors are violating U.S. intellectual property laws and the Lanham Act.

The federal government and many states have raised cigarette taxes in recent years, driving up their overall cost to consumers. So-called gray-market vendors typically import counterfeit cigarettes and smokes intended for foreign markets and sell them to consumers more cheaply than legitimate products in part because they’re untaxed.

Gray market cigarettes are made with different materials and under different quality-control procedures than cigarettes sold in the U.S. and may not display the required health warnings, Philip Morris said in the complaint. Consumers also may be “disappointed and/or confused” by the differences between the gray market cigarettes and those Philip Morris sells in the U.S., it said.