Owner Sonae Indústria confirmed the decision on Friday following consultation with the workforce.
The plant was hit by a major fire last year and Sonae said delays to reconstruction work were a major factor in its decision.
A company statement said: “The decision is the result of the long delays to the reconstruction of the factory due to political and licensing difficulties and the reduced and unsustainable capacity levels that have ensued.
“Therefore, as from today, no further manufacturing will take place at the plant and almost all the workforce will leave the company.
Sonae will continue supplying the UK market from its other plants throughout Europe.