KITIMAT, B.C. -- The union representing Rio Tinto employees in British Columbia has issued a 72-hour strike notice after nearly seven weeks of negotiations.

Unifor Local 2301, which represents about 900 workers at the smelting facility in Kitimat and the power generating facility in Kemano, have unanimously voted in support of a potential strike.

Union national president Jerry Dias says the historic member vote “speaks volumes to the culture of disrespect and unfair treatment Rio Tinto has created over many years.”

The union says it has proposed the first changes to workers' retirement income and benefit levels in more than a decade, including moving younger workers to defined benefit from defined contribution pension plans.

It also says negotiations have focused on a backlog of more than 300 grievances resulting from the company's use of contractors and refusal to hire full-time workers.

The company couldn't be immediately reached for comment.

“Senior management says they want a mutually beneficial deal that avoids a dispute, but their actions at the bargaining table tell a completely different story,” stated local president Martin Mcllwrath.

Unifor is Canada's largest private-sector union, representing 315,000 workers.

This report by The Canadian Press was first published July 22, 2021.