A Canadian court has ordered tobacco firms to pay $12.4bn to smokers in Quebec who claimed they were never warned about health risks linked to smoking.

Superior Court Justice Brian Riordan said in his decision released late on Monday that by choosing not to inform health authorities or the public directly of what they knew, the companies chose profits over the health of their customers.

The case is believed to be the biggest class-action lawsuit ever seen in Canada. JTI-Macdonald, Imperial Tobacco, and Rothmans, Benson & Hedges said they will appeal.

The judgement calls on the companies to issue initial compensation of more than $800m in the next 60 days, regardless of whether they elect to appeal. The judge will decide at a later date how to distribute those funds.

The Quebec case marked the first time tobacco companies had gone to trial in a civil lawsuit in Canada and involved two separate groups of plaintiffs: some of whom became seriously ill from smoking and others who said they couldn't quit.

'Moral conflict'

Riordan denounced the firms' actions.

"The companies earned billions of dollars at the expense of the lungs, the throats and the general well-being of their customers," he wrote.

"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?"

More than one million Quebecers were represented and argued the companies were liable because they knew they were putting out a harmful product and hid the health effects of tobacco.

The industry argued people knew about the risks of smoking and that the products were sold legally and with federal government approval and strict regulation.

"These cases are far from over," RBH spokeswoman Anne Edwards said in a statement. "We will vigorously appeal this lower court's judgement."

JTI-Macdonald said Canadians have been well aware of the health risks since the 1950s and health warnings have been on packages for more than 40 years.

The three firms will split the payout according to responsibility set out by the court - 67 percent will fall to Imperial Tobacco, 20 percent to Rothmans, Benson & Hedges, and 13 percent to JTI-Macdonald.

"These three companies lied to their customers for 50 years and hurt their right to life," Andre Lesperance, one of the lawyers representing the plaintiffs, said Monday. "It's a great victory for victims as well as for society in general."

The trial stemmed from two cases that were originally filed separately in 1998 before being certified and consolidated in 2005. The case began sitting in 2012.

Source: Agencies