WORKERS at supermarket giant Asda are stepping up their campaign for equal pay today as thousands of staff begin working “for free” for the rest of the year.

The GMB said today marks the day on which the predominantly male distribution workforce will have already earned what the mainly female retail workforce will take home in a year.

This means retail staff face 39 working days before Christmas where they will effectively be paid nothing, compared with their distribution colleagues, the union said.

GMB is pursuing an equal pay claim against the company, which it says will have huge implications in the retail sector.

National officer Nadine Houghton said: “It’s scandalous that up to 100,000 Asda retail workers will essentially be grafting for free for the rest of the year.

“The entire retail sector has been built on the structural undervaluing of women’s work, but GMB members are changing this with their historic fight for equal pay in Asda.”

An Asda spokesman said that male and female workers “doing the same jobs in stores are paid the same, and this is equally true in our distribution centres.”