TORONTO - Against the backdrop of U.S. tariffs battering local automakers, uncertainty linked to upcoming trade talks and the “incursion” of Chinese electric vehicles into Canada, the union representing nearly 19,000 Canadian auto workers says it’s bracing for the most significant labour negotiations in its history.

Talks between Unifor and the Detroit Three automakers are set to kick off Monday in Toronto as their current collective agreements are set to expire Sept. 20.