Three tobacco companies have been ordered to pay C$15.5 billion ($12 billion) in damages in Canada.

It the largest award for damages in Canada’s history.

The plaintiffs were Quebec smokers who said the companies failed to warn them of health risks associated with smoking.

Imperial Tobacco Canada, Rothmans Benson & Hedges and JTI-MacDonald vowed to appeal against the decision.

The class-action lawsuits were filed in 1998, but only recently went to trial in the courts.

The companies argued that Canadians have had a “high awareness” of smoking health risks since the 1950s.

The director of Quebec Council on Tobacco and Health, an anti-smoking lobby group, Mario Bujold, said it had been “a long process” but it was a “big victory for the victims and against the tobacco companies”.

JTI-Macdonald said in a statement: “That awareness has been reinforced by the health warnings printed on every legal cigarette package for more than 40 years.”

However, the plaintiffs argued that the companies did not properly warn their customers and failed in their general duty “not to cause injury to another person”, according to the Quebec Superior Court decision.

They represent nearly one million smokers who were unable to quit or who suffer from throat or lung cancer, or emphysema.

Explaining his ruling, Judge Brian Riordan said: “The companies earned billions of dollars at the expense of the lungs, the throats and the general well-being of their customers.

“If the companies are allowed to walk away unscathed now, what would be the message to other industries that today or tomorrow find themselves in a similar moral conflict?”