British Steel is halting production on Teesside for three weeks.
The company confirmed 300 workers at its Skinningrove site will be furloughed from 13 June "as a temporary measure".
Production at the site was temporarily paused earlier this year due to a fall in demand amid the coronavirus outbreak.
A spokesperson said it's down to a tough market.
COVID-19 continues to have a major impact on people and businesses across the world and British Steel is working hard to overcome the challenges we and our customers face.
He also said that he knew it was a "worrying time for staff" but that production would "resume at the earliest opportunity".
The firm said it was following government guidance in its manufacturing operations and thanked staff for their hard work.
We thank all our employees for their continued commitment and flexibility. This has been a challenging time for all of us, and we couldn’t have continued to safely fulfil customer orders and support the UK’s economic recovery without their dedication.
Cllr Mary Lanigan, Leader of Redcar & Cleveland Borough Council, said:
“We remain confident about the future of steel production in Redcar and Cleveland. Trading conditions across the world are challenging at the moment, but as this starts to ease, we hope to see production resume again and British Steel’s renowned product help rebuild economies.
“In the meantime, our thoughts are with everyone at the company and we will do everything we can to support the company and all other businesses in Redcar and Cleveland as they recover from the effects of the COVID-19 outbreak.”