Unifor, the union representing hourly employees at the historic plant, had expected assembly to continue to Dec. 19 but said it now has been told production will end Dec. 17.

The global auto industry will produce 88.8 million cars and light trucks this year, an almost six per cent drop from a year ago, according to researcher IHS Markit. In Canada, GM, Ford and FCA plan to eliminate production jobs this year or next.

The UAW said it secured an additional US$4.5 billion in investments from the company but released no other details. A council made up of officers from union locals representing FCA workers must approve the proposed four-year pact before it's presented to members for ratification. The council will review the agreement on Wednesday

In its grievance, Unifor insisted Nemak must keep the plant open until the current labour contract expires in 2022. Nemak wants to shutter the plant in mid-2020.