Workers at Wilko's Distribution Centre in Monmouthshire are going on strike next month.
The GMB Union has revealed the dates almost 2,000 staff will walk out over forced weekend working.
Around 1,800 GMB members at two Wilko distribution centres – in Magor, Monmouthshire and Worksop, Nottinghamshire – will strike as follows:
· From 06:00 on Friday 11th October 2019 until 05.59 on Saturday 12th October 2019
· From 06:00 on Monday 14th October 2019 until 05:59 on Tuesday 15th October 2019
The industrial action is expected to cripple Wilko deliveries to stores across the UK.
Gary Carter, GMB National Officer, said: "It is sad that it has come to this. We have done everything we can to try to negotiate a reduction in the amount of weekend working, but the offer from management is not acceptable.
"Wilko has always considered itself a family company - yet they're forcing contracts on staff that will seriously impose on family time and workers' wellbeing.
"GMB members will stand together and show Wilko management how strongly we feel about these harsh new contracts."
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