The government has been accused of blocking EU legislation aimed at improving equal pay and employment rights.

Ministers have insisted that equal pay and basic employment rights are only extended to those temporary workers who have held the same post for over a year.

But the TUC has argued that the new benefits would not be felt by three quarters of Britain's 800,000 agency staff who are not kept in employment for 12 months.

"The government and business case for a qualifying period for agency workers rights confuses 'flexibility' with 'low cost'," said general secretary Brendan Barber.

"Research by temp agencies themselves shows that employers use temps because of the natural flexibility they provide, not to do things on the cheap.

"There is no solid argument for denying agency temps fairness at work from their first day on the job."

A spokesman at the Department of Trade and Industry denied the claims.

"Our key concern is to ensure that any directive protects agency workers without putting their jobs at risk," he said.