A chemical plant on Teesside is facing closure after "decades of significant under investment", putting jobs at risk.
More than 220 people are employed at the Ineos acrylonitrile manufacturing plant at Seal Sands.
The company said if the closure went ahead not all jobs would be lost because there would be other activities at the site.
Managers will be consulting with workers "on any viable alternatives".
The Unite union said the region could "ill-afford to lose these highly skilled jobs" and is calling for talks with the company.
Ineos said that since it took over the plant in 2008 it had invested almost €200m (£178m) in the site, but it would require another €200m just to meet Ineos standards and environmental regulations.
CEO Paul Overment said the decision was made "with a heavy heart" and was due to "decades of under investment".
"Manufacturing assets need constant renewal if they are to survive", he said.
"The last 10 years have proven that it is almost impossible to play catch-up and the lesson for us and other UK manufacturers is that constant reinvestment is vital for long term prosperity."
Alex Cunningham, Labour MP for Stockton North, described the news as "extremely disappointing" and a "huge blow" for workers and the local economy as a whole.
He said: "It is vitally important that the workforce is supported throughout the consultation process and helped into alternative employment where possible."