A US federal judge has decided that a lawsuit being brought against the tobacco industry can be conducted as a nationwide class action.

It simply has no legal basis and is contrary to US Supreme Court precedent

William Ohlemeyer Philip Morris lawyer

This means that those who brought the case initially could now represent a far larger group of people and any damages could be enormous.

In a written statement Judge Jack Weinstein said the class action could include anyone living in the US who smokes or smoked the defendant companies' cigarettes and who has been diagnosed with a disease such as lung cancer, tongue cancer or emphysema from 9 April 1993.

Any punitive damages awarded would be distributed on a pro rata basis by disease to members of the class who could show proof of their sicknesses.

Appeal hopes

The companies listed as defendants in the suit, known as Simon II, include Philip Morris, RJ Reynolds, Brown & Williamson - a unit of London-based British American Tobacco - and Lorillard Tobacco.

Shares in tobacco companies were trading lower on Friday in response to the move.

The class action excludes certain people, such as those who have obtained settlements or judgments against any of the defendant companies.

The industry has 10 days to appeal.

William Ohlemeyer, a lawyer for Philip Morris said: "Federal courts across the country have overwhelmingly rejected class actions in tobacco cases, and we believe this case will be treated no differently by the Court of Appeals.

"It simply has no legal basis and is contrary to US Supreme Court precedent," he added.

RJ Reynolds Tobacco, whose brands include Camel and Winston, said it believed the appeals court should and would overturn the order.