The company, Change, says the scheme is voluntary and intended to help shoppers choose the right size for their purchases.

But workers complain they are pressured to wear the tags which show both the wearer’s bust circumference and cup size.

One worker complained: “We have dirty old men coming into the shop looking at my cup size.

“Why should everyone get to know that? Guys selling underwear don’t have to show their size.”

Susann Haglund, CEO of Change, said the tags had originally been suggested by the employees themselves.

They were intended to aid customers in their choice by showing them what size might be right for what body shape.

“I don’t get why this would be seen as demeaning in any way. I am sure there are those that feel that way, but it is completely voluntary to wear a name tag with your cup size,” she said.

But the Commercial Employees’ Union say the tags could be illegal and they are threatening to sue the company.