Britain has been involved in a Brussels battle over giving temporary workers the same rights as permanent staff.

Despite union pressure, the UK is resisting new EU regulations to extend employment protections over pay and conditions to all workers.

However the government has been fighting to persuade fellow member states to delay the change, which the private sector fears could put 250,000 jobs at risk.

Only four of the 27 EU members were thought to be firmly opposed, meaning Britain could be forced to comply under qualified-majority voting at a council of ministers meeting on Wednesday.

A source close to business secretary John Hutton told Tuesday's Times newspaper that the government was unhappy at the linking of the issue by Portugal to a debate on the working-time directive which restricts employees' hours.

"The agency workers' directive, as currently worded, could have a negative impact on employment," the source said.

"We are committed to the principle of agency workers' rights, but the directive brings it in sooner than is in Britain's interest.

"The two directives have been linked for the sake of expedience, rather than because they are related. We are trying to unlink them."

But TUC general secretary Brendan Barber said the government should drop its opposition.

"Agency workers have been vulnerable to real injustice for far too long," he said. "The government should understand the strength of union feeling on this issue.

"There will be a political price to be paid if the UK government simply follows the business agenda and not the social justice agenda and they fail to grasp this new opportunity to break the EU deadlock."

However shadow business secretary Alan Duncan said: "This is yet another EU attempt to impose a 'one-size-fits-all' solution.

"Of course all temps in the UK need to be paid a fair rate and legislation to help this is welcome. However, this would be bad for individuals, bad for companies and bad for the economic health of the country."

And CBI deputy director general John Cridland added that: "A quarter of a million UK jobs are on the line if this draft directive goes through. The government has, rightly, been rock solid in opposing this legislation."

Meanwhile Britain was on Tuesday set to resist moves to extend Brussels' regulatory powers over national financial markets.

At a meeting of EU finance ministers chancellor Alistair Darling was set to reject Italian proposals for a one-size-fits-all pan-European regulatory approach.