Tata Steel is to push ahead with plans to close both blast furnaces at its Port Talbot works in south Wales.
The move is expected to lead to the loss of up to 3,000 jobs.
The decision follows a meeting between Tata executives and the Community, GMB and Unite unions at a London hotel today.
It is expected to be formally announced by Tata tomorrow.
Tata is planning to replace the blast furnaces – which produce new steel from iron ore – with a modern electric arc furnace.
This will produce usable steel from scrap metal. It will be more environmentally friendly to operate, but require a smaller workforce.
Last year, the government said it would support the £1.25bn plan with up to £500m of public money.
A plan put forward by the GMB and Community had argued that one of the blast furnaces should be kept open for a transitional period, alongside a new electric arc furnace, to safeguard jobs and preserve the UK’s ability to make new steel. However, Tata has been reluctant to do this because of the costs involved in keeping the existing furnaces and support operations going.
Tata Steel’s Port Talbot plant is the largest steelworks in the UK, it currently employs 4,000 of the company’s 8,000-strong UK workforce.
These plans would see 75% of of the workforce at Port Talbot lose their jobs.
It is understood that a large proportion of these 3,000 jobs will be gone by September of this year.
The first job losses are likely to begin in April, with more following in September.