Amazon workers are to stage fresh strikes in an escalation of a dispute over pay.
The GMB union said more than 500 of its members at the online giant’s site in Coventry will walk out for three days from April 16 and again from April 21-23.
The six days of action follow a series of stoppages earlier this year.
The GMB also announced it will be balloting its members at five more Amazon sites across the Midlands for strikes over pay.
Voting started on Friday at the sites in Leicestershire, Nottinghamshire, Staffordshire and Warwickshire.
Amanda Gearing, GMB senior organiser, said: “Industrial action is growing and this could fast become a summer of strike chaos at Amazon.
“Three months ago Amazon told our members there was no money left for pay rises, yet through pressure, campaigning and strike action we’ve forced Amazon to sit up and take notice.
“Six further days of strike action in Coventry is a clear statement from our members they are worth more. They will not accept a pay rise of pennies from one of the world’s wealthiest corporations.
“With workers at five further sites starting ballots for industrial action this month, it’s clear Amazon need to urgently get serious and talk pay with GMB now.”
Amazon said that from next week, the minimum starting pay for its employees will increase to between £11 and £12 an hour depending on location.
A statement said: “We regularly review our pay to ensure we offer competitive wages, and we’re pleased to be announcing another increase for our UK teams.
“Over the past seven months, our minimum starting pay has risen by 10%, and by more than 37% since 2018. We also work hard to provide great benefits, a positive work environment and excellent career opportunities.
“These are just some of the reasons people want to come and work at Amazon, whether it’s their first job, a seasonal role or an opportunity for them to advance their career.”