Local authorities and the NHS could be forced to fork out millions of pounds after a landmark ruling over equality for low-paid women.
The critical equal pay test cases at the Court of Appeal resulted in a judgment that pay protection schemes that perpetuate sex discrimination were unlawful.
This paves the way for thousands of pay claims to be launched in employment tribunals throughout the country, principally against local authorities and NHS trusts.
But the three judges who heard the cases said the effect of the ruling extended beyond the public sector and was likely to affect the way in which employers, employees and trade unions approach equal pay, job evaluation and changes to pay and grading.
Lord Justice Mummery, who delivered the ruling, said: "The sums involved in the proceedings are very large indeed."
The cases were heard by the Court of Appeal and concerned two separate groups of female claimants – among them cleaners and school crossing patrol staff – employed by two councils in the North East.
Speaking after the ruling, equal pay specialist, Cloisters' barrister Rachel Crasnow, said: "The court's ruling, that discriminatory pay protection is unlawful, could pave the way for thousands of new equal pay claims against local authorities and the NHS. This would be in addition to the thousands of equal pay claims which are already in the system."