Imperial Tobacco today said closing its factories in Nottingham and Naples would help save £300 million a year.
Up to 900 workers - including 540 in Nottingham - face the axe as part of the plans.
The firm said the savings - which would come into effect from September 2018 - were "necessary" for the future of the company.
Chief executive Alison Cooper said:
These projects are an essential part of securing the sustainable future of the business.
The prospect of job losses is always regrettable and we will be doing all we can to support employees and ensure that they are treated in a fair and responsible manner.
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