Hundreds of thousands of men working in the the public sector are facing salary cuts of up to £15,000 a year as equal pay agreements take effect, The Times has learnt.

Compensation claims for up to 1.5 million workers could cost the taxpayer more than £10 billion and mean that male staff lose up to 40 per cent of their salary.

Up to 700,000 female council workers, a similar number of NHS workers and tens of thousands of teaching assistants and Ministry of Defence staff are now eligible for equal pay settlements stretching back over six years.

Over the past two years, unions have reached hundreds of compromise agreements with local councils to help to protect male workers’ pay and jobs while getting a good deal for women. But aggressive no-win, no-fee lawyers are now unpicking the agreements by winning higher compensation payments for thousands of individual claimaints. The result is a tougher squeeze on male pay, with some men having their salary hugely reduced.

Higher-paid white-collar female workers and social services staff could also lose money so that salary rises for lower-paid women are affordable.

The Government is so far refusing to bale out the employers, although ministers are worried about the escalating costs that could lead to higher council tax bills next year and further cuts in NHS services. Phil Woolas, the Local Government Minister, is considering legal measures to make agreements binding, though these could fall foul of the Equal Pay Act 1970 and a subsequent EU ruling in 2003.

The unions claim that no-win, no-fee solicitors are now undermining industrial relations in the public sector as lawyers try to renegotiate settlements. Union officials across the public sector are now having to agree to settlements where men’s pay will be cut.

Brian Strutton, of the GMB union, said that men were also taking councils to court. “People have to compromise, otherwise it is unaffordable,” Mr Strutton said. “As part of the compromise we sometimes have to bring down male earnings. But it only then takes one woman to want more to break the whole agreement.”

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