Unifor National President Jerry Dias has stepped down after more than eight years at the helm of Canada’s largest public-sector union amid unspecified health issues. 

Dias had been on medical leave since Feb. 6. He notified Unifor’s National Executive Board on Friday that he would be retiring effective immediately, according to a release from the organization. The National Executive Board plans to meet in the coming days to discuss the next steps and the constitutional requirements around the vacancy.

“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,” Dias, 63, said in the release. “I have all the confidence the leadership, staff and locals will continue to build Unifor into a bold and progressive force for working people.”

Dias was a leading advocate for Canadian workers during a tumultuous time that included trade wars with the U.S. and renegotiation of the North American Free Trade Agreement, a key demand of then-U.S. President Donald Trump. 

In 2020, Dias negotiated an agreement to save Ford Motor Co.’s only vehicle assembly plant in Canada. His union also negotiated to keep a General Motors Co. plant in Oshawa, Ontario, that had been slated to close, albeit as a parts manufacturing facility with just 300 of the 3,000 original workers.