A group of Canadian General Motors dealers said Friday they will sue the automaker in an effort to keep their dealerships open.

The 12 dealers — 11 in Ontario and one in Prince Edward Island _ are among almost 250 that GM Canada plans to close within the next year.

General Motors, whose products include these Pontiac G6 and Chevrolet Malibu sedans seen at a plant in Michigan, is dropping almost 250 Canadian dealerships.General Motors, whose products include these Pontiac G6 and Chevrolet Malibu sedans seen at a plant in Michigan, is dropping almost 250 Canadian dealerships. (Paul Sancya/Associated Press)

They claim the company's move, announced in May, breaches a contract that the company promised to renew as long as they met performance expectations.

One of the claimants is Robert Slessor Pontiac Buick in Grimsby, Ont. Slessor said his business has exceeded the requirements laid out in the contract. The dealership has been in his family for 60 years and Slessor said he's determined not to lose it.

GM plans to cut more than one-third of its Canadian dealerships by October 2010 to reduce costs and streamline its business. It also is eliminating about 1,100 dealerships in the United States.

With files from The Canadian Press