The Whyalla steelworks in South Australia has started cutting hundreds of jobs after its blast furnace failed to restart.

Reports place the number of positions at risk at 500 or more, and some say over 600. The full scale of the cuts is not yet clear.

At least 146 workers have been confirmed as having lost their jobs permanently.

The furnace shutdown forced the company to make the cuts. The steelworks has yet to make an official announcement about the job losses, but one was expected soon.

The job cuts follow the failed restart of the blast furnace at the site.