TORONTO -- Ontario Premier Doug Ford says the closure of the General Motors plant in Oshawa, Ont., is "done" and there's nothing the government can do to change the automaker's plan.

Ford says he asked GM in a phone call on Sunday whether there was anything the province could do to keep the plant open, and was told it could not.

He says instead, the province will immediately bolster unemployment insurance and retraining measures to help the nearly 3,000 workers who will lose their jobs.

The Oshawa plant is one of five in North America that the automaker plans to shut down as it restructures to cut costs and focus more on autonomous and electric vehicles.

The union representing the Oshawa auto workers says it will put up what it calls "the fight of our lives" to keep the plant open and save thousands of jobs.

Ford says the province has called on the federal government to extend employment insurance eligibility by five weeks to a maximum of 50 weeks.