The Board of Equal Treatment effectively ruled last month that price differences between men's and women's haircuts were illegal. It ordered a salon advertising women's haircuts for 528 crowns ($94) and men's haircuts for 428 crowns plus an extra fee for long hair to pay 2,500 crowns ($450) to a woman who had filed a complaint.

Now, a trade organisation for hairdressers has called the decision absurd, saying it will become a nightmare to set prices for customers and warning of "pricing chaos".

"It takes, quite simply, longer time with women," Connie Mikkelsen, chairwoman of the Danish organisation for independent hairdressers and cosmeticians, said in a statement on Monday.

The board's decision has been appealed and a court will determine whether hairdressers need to find a new way to charge for their services, in the length of time, or the standard of the cut.

"Measuring time will lead to a discussion of hair length - what is medium length, and what is long. It will end in a series of conflicts with customers," Mikkelsen said.

Nordic countries consistently hold some of the highest rankings in global gender equality indices. Denmark ranked 7th out of 135 countries in the World Economic Forum's global gender gap index which benchmarks national gender gaps on economic, political, education and health criteria.