WASHINGTON - Citing an ‘extraordinary economic environment,’ ArcelorMittal, the world’s largest steel maker, has announced plans to indefinitely lay off 978 workers at its Indiana Harbour West mill plant in July.

Although the mill’s iron-producing operations will also be suspended indefinitely, another blast furnace at the East Chicago mill in northwestern Indiana will remain in operation, the Luxembourg-based company owned by Indian steel czar Lakshmi Mittal said Wednesday.

The company said it alerted the United Steelworkers (USW) and other stakeholders of the action Tuesday in accordance with the Worker Adjustment and Retraining Notification Act.

A letter from the company posted on USW Local 1011’s Web site said the layoff would be temporary and for an indefinite period of time during a 14-day period starting July 12. USW Local 1011 represents employees at the Indiana Harbour West facility.

ArcelorMittal will idle iron-producing operations at Indiana Harbor West until market conditions improve. Iron production will remain at Indiana Harbor East’s No. 7 blast furnace, according to a statement from ArcelorMittal’s US headquarters in Chicago.

ArcelorMittal is maintaining temporary global production cuts at a level of about 45 percent, as announced April 29.

‘This was a difficult decision to make, but the company is being forced to respond to the extraordinary economic environment we are facing,’ the statement said.

‘We will be carefully monitoring the situation, and we look forward to many of our employees returning to work as soon as it is warranted by market conditions.

‘This development is in no way a reflection on the professionalism and dedication of our Indiana Harbor employees. ArcelorMittal appreciates their efforts and assistance during this challenging period. We will continue to work with the USW to minimise the impact on our employees and their families.’

Pete Visclosky, Democrat member of US Representatives from Indiana said in response to the announced layoff: ‘I am deeply saddened by today’s terrible news, and my thoughts and prayers are with the workers who are being laid off and their families.

‘I will continue to do everything I can to stabilise steel to protect steelworker jobs, help our economy recover, and create new opportunities in Northwest Indiana.’