Smokers, who have been puffing on discount cigarettes in an effort to get a price break, forced the biggest U.S. cigarette maker to make concessions Friday as Philip Morris USA said it will fight back against the low-cost brands.

One cigarette analyst said the move amounts to "full-scale war" among cigarette manufacturers, who already are worried by Clinton administration plans to hoist cigarette prices further with a tax of about $2 a pack.

Philip Morris said Marlboro and its other premium brands "remain strong and profitable," with Marlboro holding over a 22 percent market share in the $45 billion domestic cigarette market.