Employers who pay staff less than the National Minimum Wage (NMW) are subjecting their employees to conditions akin to slavery, according to Aspect.co.uk managing director Will Davies.

Davies’s comments come as government sources named and shamed 48 organisations for failing to pay workers the minimum required wage. It currently stands at £6.50 per hour for those aged 21 and over. For workers aged between 18 and 20 it is £5.31 and £3.79 for 16 and 17-years-olds.

Sports retailer Foot Locker and franchised hair salon Toni & Guy are among the worst offenders; the former owing a total of £16,718.25 to 600 workers.

The announcement is the latest in a string of attempts by the HMRC to name and shame employers who repeatedly fail to pay staff NMW. Since 2013 210 businesses have been named and many face fines of up to £67,000.

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Entrepreneur and self-proclaimed employment campaigner Davies has called for repeated offenders to be jailed. While he opposes scrapping zero-hours contracts, which he says would encourage “illegal labour”, he is resolute in his views around NMW.

“It beggars belief that employers are willing to cut their wage bill and exploit young people by not giving them £6.50 per hour – which is still not enough,” he said. “Failure to pay an employee the NMW is slavery and as far as I’m aware, those who impose this barbaric act are locked behind bars.”

A spokesman for fashion retailer French Connection, another business named in today’s announcement, apologised to those workers involved but attempted to play down the significance of the underpayments.

“French Connection co-operated fully with HMRC in assessing the amounts involved and paid the arrears at the earliest possible opportunity,” he said. “French Connection fully supports the UK Government’s minimum wage legislation and we are apologising to our staff for the inconvenience.”

Further reading on HR: Is it fair to use zero-hours contracts when growing your business?