Anglesey Aluminium Metal says it has advised employees that there is a "strong likelihood" its operation in Holyhead will close.
In 2009, the company closed its smelting operation and 400 members of staff were made redundant. Since then around 100 employees have continued to work on the site.
– Spokesperson for the Anglesey Aluminium Metal
Increased competition, a rise in material costs and a drop in demand for its products mean that the business is facing severe operating losses and joint discussions have been underway to try and find ways to ensure the viability of the remelt operation.
The company says the consultation process will continue and as soon as it has come to a final decision then employees and various stakeholders will be informed.