ON CALL: Britain’s GMB union is revealing the darker side of Black Friday weekend, offering Asos employees access to a 24-hour, confidential hotline if they’re feeling exploited during the busy sales period.

GMB, which has in the past raised issues with Asos regarding working conditions, is encouraging employees of the British online fashion retailer to report any problems or poor work practices. The union, which issued a statement today, has said calls will be anonymous and whistleblowers protected.

The retailer is taking part in Black Friday discounting, offering up to 20 percent off of its apparel, accessories and shoes.

“Asos…appears to have forgotten that as an employer their first responsibilities are delivering a safe, decent workplace and fair terms and conditions for their own workers,”said Neil Derrick, regional secretary of GMB.

“No Friday should be a Black Friday for workers — and too many Asos workers have reported dark days when employed by the company. We encourage anyone with concerns to call. They will be able to speak in their own time and in the strictest of confidence.”

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Earlier this year, GMB started asking Asos questions, following investigations by Buzzfeed and the BBC, which accused Asos of unfair working conditions. The retailer robustly defended itself following both media companies’ reports.

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The retailer declined to comment.

Meanwhile, workers at Topshop’s online distribution depot have announced plans to strike on Nov. 28, Cyber Monday, in a dispute over their hourly wages.

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