Protests are to be staged outside Amazon warehouses to highlight complaints about working conditions at the retail giant.
The GMB is organising demonstrations at five sites on Friday, claiming some conditions are “inhuman”.
General secretary Tim Roache said: “We’re standing up and saying enough is enough. You’d think making the workplace safer so people aren’t carted out of the warehouse in an ambulance is in everyone’s interest, but Amazon seemingly have no will to get round the table with us.
“Working people and the communities Amazon operates in deserve better than this. That’s what we’re campaigning for.”
Amazon said in a statement: “Amazon has created in the UK more than 25,000 good jobs with a minimum of £9.50 an hour and in the London area, £10.50 an hour on top of industry-leading benefits and skills training opportunities.
“All of our sites are safe places to work and reports to the contrary are simply wrong. According to the UK Government’s Health and Safety Executive, Amazon has over 40% fewer injuries on average than other transportation and warehousing companies in the UK.
“We encourage everyone to compare our pay, benefits and working conditions to others and come see for yourself on one of the public tours we offer every day at our centres across the UK.”
Protests will be held in Milton Keynes, Warrington, Peterborough, Swansea and Rugeley.