Marlboro manufacturer Philip Morris has lost a key court ruling in the US over the marketing of ‘light’ cigarettes, paving the way for a raft of legal action against the tobacco giant and its rivals.

The US Supreme Court has ruled that smokers can sue Philip Morris over claims that its Marlboro Light and Cambridge Light brands were less harmful than regular cigarettes – claims that the plaintiffs say are misleading.

They claim that although the ‘light’ variants contain less tar and nicotine, the company wa aware that some smokers would hold the smoke in their lungs for longer and therefore gain no health benefits from smoking ‘light’ brands.

The case will now go ahead in the Maine district court and is sure to be closely watched by other major tobacco groups.

Philip Morris, which is owned by Altria Group, has warned that legal action could deter manufacturers from marketing less damaging ‘light’ brands.