The US group said 6,500 staff would go over the next year as part of a cost-cutting drive, following 1,800 redundancies earlier this year.

Alcoa said the restructuring would result in costs of $245m to $275m, but would lead to annual savings of $195m.

Alcoa added it expected its profits for the second quarter of the year to come in at $219m after tax.

Locations trimmed

The company has been battling against a downturn in trade from automotive, packaging and European markets, as well as higher costs overall in recent years.

Pittsburgh-based Alcoa is also closing plants or disposing of assets in 121 locations in North America, Latin America, Europe and Australia.

Meanwhile, the firm is "exploring options" for its aluminium smelting facility in Maryland which could close as a result of high local power prices.

If an acceptable deal cannot be reached, Alcoa has said it will mothball the plant.