British employers could be obliged to limit all workers to a 48 hour week as Euro MPs debate reforms to strengthen the Working Time Directive.

At present, Britain is the only European nation which makes wide use of an 'opt-out' clause, which allows employees to sign away their rights under the directive.

MEPs will however today debate whether to end the right to opt out within three years, as part of a general overhaul of the 1993 legislation.

British employers are dismayed by the moves, saying that requiring workers to put in longer hours is a vital part of workforce flexibility. But unions have complained that the opt-out is regularly abused by companies which force people to work long hours.

The debate begins today on the plans to phase out the opt-out over three years, and to average the 48-hour working week over 12 months rather than the present four months.

The changes proposed in the European Parliament by Alejandro Cercas, a Spanish socialist, also include counting on-call time as working time in most cases.

Labour MEPs are backing the reforms, while Conservative and Liberal Democrat MEPs were said to be opposing them as damaging for business.

Stephen Hughes, a Labour MEP who speaks for the Socialist Group on employment issues, told the BBC Radio 4 Today programme: "We feel that, in principle, it is wrong to have an opt-out for health and safety legislation.

"The European Court of Justice ruled very clearly in 1996 that this is a health and safety directive. We don’t want an opt-out, and what we do want is a proper balance between work and family life in Britain and every other member state of the EU."

But Philip Bushill-Matthews MEP, the Conservative employment and social affairs spokesman, said that it was none of the EU's business how long British workers had to work. "I don’t accept it should be up to Brussels to determine how many hours people should or shouldn’t work," Mr Bushill-Matthews told Today.

"I agree that quality of life is an issue, but why should politicians in Brussels decide that the way for people to get quality of life is to follow rules on a one-size-fits-all basis laid down at EU level? It’s sheer nonsense."

He accused Labour of pursuing "two completely different agendas", with the Government claiming to be fighting to preserve the opt-out, while allowing Labour MEPs to vote to scrap it.

The TUC is backing the proposed changes, which it said go a long way to meet the fears of employers. Brendan Barber, the TUC general secretary, said: "This issue has been deadlocked for too long. The European Parliament should accept this sensible compromise.

"It certainly does not go as far as we would like, but it does meet the key objection from most employers who encourage their staff to sign an opt-out. Employers say they need the flexibility to be able to cope with the peaks and troughs of workload. An annual average does precisely this."

Mr Barber said ending the opt-out from the directive would strike a blow against the UK"s long hours culture.

John Monks, general secretary of the European TUC, told the Today programme: "I don’t buy the general argument about this being new dynamic Britain versus old, sclerotic continental Europe. I think it is a question of giving people a balance in their life and the European way is for a balance, it’s not for working until you drop."

But the Engineering Employers’ Federation said the proposals were "damaging" and could hit the UK’s flexible labour market. David Yeandle, deputy director of employment policy, said: "The Government must continue to stand firm on this important issue."

The issue will go to a plenary vote in Strasbourg tomorrow and the proposal will then go back to the Council of Ministers for consideration by member states.

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