The taconite mine and pelletizing plant will now be closed until August 6, while employees will be called back from layoffs beginning July 27.

"We will be taking all precautions and protocols necessary to ensure a safe and orderly restart," said the Luxembourg-based global steel and mining company.

ArcelorMittal operates the plant and owns 62.3% of the venture, alongside Cleveland-Cliffs at 23% and U.S. Steel with 14.7%.

Hibtac, which produces 7.8 million tonnes of taconite annually, and mines about 29 million t of ore annually, had to lay 650 employees off in April as the shutdown began.