UNION leaders have begun ground-breaking legal action in a bid to secure a £10million pay rise for 4,000 county council workers.

UNISON, which represents white collar public sector workers, has lodged its claim on behalf of mainly female teaching support staff using new Government legislation.

It believes it can prove they do as important-a job for the county council as male technical staff working in the Environment Directorate -- which deals with everything from highways maintenance to recycling -- and who get paid up to £2,500 more a year.

The threat of legal action, using the new Equal Pay Act, has already prompted Blackburn with Darwen Council to launch a review of salaries to ensure it is not subject to similar claims.

UNISON has lodged its claim with an employment tribunal in Manchester but has agreed to leave it on ice until negotiations with the county council over pay rises have been complete.

The legal action is the largest equal value pay claim to be made in Europe, and one of the first in Britain.

A total of 990 teaching assistants are named, but the salaries of 4,000 full and part-time workers will be affected.

The staff include nursery nurses, special support assistants, and learning and classroom assistants.

The union said the average full-time wage was little more than £8,000 a year.

UNISON national secretary for local government Heather Wakefield said: "School support staff are among the most undervalued in local government. These equal pay claims demonstrate the need for local authorities to carry out urgent pay audits and bring the pay structures in line with the Equal Pay Act."

North West regional secretary Frank Hont,said: "By taking this case, UNISON is demonstrating its commitment to attacking the gender pay gap."

A tribunal in Newcastle recently approved a claim by hospitals support staff that they deserved the same pay as NHS decorators and maintenance men.

A Lancashire County Council spokesman said: "The county council has been discussing the position with Unison during the last two to three months and is committed to continuing these discussions with a view to reaching an agreed outcome without the need for a tribunal hearing.

"More than 600 Lancashire schools could be affected by the outcome and their views need to be considered.

"The process of consultation and discussion will take several months."

"This is a large group of employees and the problem will be difficult to resolve." Among the issues to be considered will be who exactly funds any pay rise, the county council or schools from within their budgets.

According to UNISON, in local government, women earn on average 66 per cent of their male counterparts' pay.

Donna Hall, executive director for resources at Blackburn with Darwen Council, said money had been allocated in this year's budget to review salaries.

Ribble Valley MP Nigel Evans said: "If they are doing equal work, they deserve equal pay. But I would hope that Lancashire County Council and the unions can get together and sort out a common sense solution.''

Hyndburn Labour MP Greg Pope said: "This legislation has been in place for some time. For once I am in agreement with Nigel Evans."