Michelin has announced it will close its tyre factory in Ballymena, Northern Ireland, because of high energy costs, resulting in the loss of 860 jobs.
The company said it is "running down" the plant, which produces truck tyres, ahead of its eventual closure in mid-2018.
Managers of the factory, which has been open since 1969, have been warning for a number of years that high energy costs were making production increasingly unsustainable.
The move is part of Michelin's restructuring plan that will see investment in its facilities in Dundee and Stoke on Trent.
The campaigning group Manufacturing NI, which represents 550 Northern Ireland manufacturers, believes that energy prices in the country are prohibitively high which damages local businesses.
It said costs were 15-20 per cent higher in Northern Ireland than the Republic.
Unions have repeatedly called for government action to address high energy costs and capital support to modernise the plant.
Union bosses have also warned that in addition to the 860 direct job losses, 500 contractors who work with Michelin will also be affected, along with many other local businesses whose trade relies on the plant.
"Today's news is a tragic blow for the employees at Michelin Tyre,” said Northern Ireland Secretary Theresa Villiers.
"The announcement represents the closure of a long-standing and valued employer in Northern Ireland."
Ian Paisley, MP for North Antrim where Ballymena is based, said: "For North Antrim this means the loss of millions of pounds of wages annually and is, frankly, hard to come to terms with.
"The North Antrim factory has put up a valiant fight, but today they have bowed their head."
Michelin said the decision to bring the factory to a close was made in light of the ‘significant downturn in demand’ for truck tyres in Europe since the financial crisis of 2007, which has seen the market decrease by over five million tyres.
"This reduced market has been made even more challenging by the huge influx of tyres made in Asia, which have doubled in the last few years, and increased competition,” it said.
"As a result, there is a strong need to reduce over-capacity and to concentrate Michelin truck tyre production in larger, more competitive sites.
"Despite great efforts and progress being made in previous years, other European plants are still more competitive than Ballymena.”
Michelin said it would provide £5m to support employment opportunities in Ballymena and will commit to helping employees find other jobs.