The suit, which had been planned under legislation introduced in March, claims damages for past and ongoing health-care costs.

The province claims tobacco-related costs currently total more than $1.6 billion per year in Ontario and that smoking accounts for the deaths of about 13,000 Ontario residents annually.

When he introduced the legislation in March, Attorney General Chris Bentley said taxpayers shouldn't have to pay for health-care costs if they are caused by the alleged wrongdoing of others.

British Columbia, New Brunswick, Newfoundland and Labrador, Nova Scotia, Saskatchewan and Manitoba have all passed similar legislation.

The first lawsuit against tobacco companies was pursued by four U.S. states in the mid-1990s, and led to the 50-state agreement in 1999 in which the industry agreed to pay $246 billion over a 25-year period for health-care costs that resulted from the use of its products.