Union in Amazon conditions protest
The GMB claimed the firm was denying staff the right to union representation and collective bargaining.
National officer Paul Clarke said: "Where Amazon differs from other retailers is its refusal to pay proper taxes and its treatment of workers."
Amazon said: "We are proud of providing our associates with a safe and positive working environment, which includes on-the-job training and opportunities for career progression.
Amazon said it employs more than 5,000 permanent employees across the UK as well as thousands of temporary staff, adding it paid "all applicable taxes in every jurisdiction that it operates within".
The protests will be held outside several sites, including Slough, Swansea, Doncaster and Glenrothes.
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