A US federal appeals court Friday ruled the tobacco industry had deceived smokers by labeling some cigarettes as "light" when they posed just as high a health risk as other brands.

The appeals court confirmed a ruling by a lower court in August 2006 that tobacco companies lied for years about the dangerous effects of such cigarettes.

And it upheld the earlier decision that the companies must remove misleading statements such as "light" or "natural" from cigarette packets.

"We affirm in large part the finding of liability," the Washington appeals court said in its ruling in the case which pitted the US government against several powerful manufacturers including Philip Morris and Reynolds.

"The court had before it sufficient evidence from which to conclude that defendant's executives ... knew about the negative health consequences of smoking, the addictiveness and manipulation of nicotine," the appeals court said.

The company bosses also knew about "the harmfulness of second smoke and the concept of smoker compensation, which makes light cigarettes no less harmful than regular cigarettes and possibly more."

Thus the appeals court said the lower tribunal was not mistaken in its ruling "imputing to defendant's executives knowledge of the falsity of their statements."

But the court rejected pleas to force the tobacco companies to fund a national anti-smoking campaign or to pay a fine equivalent to the profits raked in from light cigarettes.

It is likely the case will now be appealed before the Supreme Court.