Sports Direct owner Mike Ashley, pledged on Thursday (31 December) to increase the wages of all lowest-paid staff in the new year. Ashley has promised to spend £10m a year to raise wages by around 15p per hour, starting on January 1 2016.

Speaking to the Daily Mirror, Ashley said "I want to see Sports Direct become the best high street retail employer, after John Lewis. I realise this is ambitious and it won't be easy but I believe that as a FTSE 100 or even 250 company we have a responsibility to set a high moral standard."

The move comes after Sports Direct and Ashley came under heavy criticism for the treatment of lower-waged staff. An investigation found that warehouse staff were subjected to humiliating searches and thousands were effectively paid below the minimum wage. Earlier in December 2015, Ashley announced a review into working conditions.

Workers aged 21 will earn £6.85 an hour from January 1 2016, up from £6.70, while 18 to 20-year-olds will earn £5.45 instead of £5.30.

Ashley continued: "Several thousand Sports Direct staff receive life-changing bonuses each year – but we have an obligation to our whole workforce. We're putting our money where our mouth is and have notified the City we will be spending £10m ensuring all employees are above the minimum wage."

In July, Sports Direct reported a 20.5% leap in pre-tax profit over its 2015 financial year. It has been criticised in the past for its use of zero-hour contracts. Around 15,000 workers on zero-hour contracts will benefit from the wage increase, as will 4,000 agency staff at its depot in Shirebrook, Derbyshire.