Announcement comes after the union chief went on medical leave
The 63 year old announcing he is stepping down as head of the Canada's largest private sector union.
Dias was originally expected to retire at the Unifor convention in August.
The Unifor board will meet in the coming few days to determine its next steps.
In a statement the union chief says "After eight and a half years I can proudly say we have built an incredible organization and made Unifor the influential and successful union it is today. I have all the confidence the leadership, staff and locals will continue to build Unifor into a bold and progressive force for working people from coast to coast to coast."

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