Britain’s opt-out from the maximum working week of 48 hours imposed by the EU is under threat after a Labour MEP joined in opposing the exception, in direct conflict with Gordon Brown.

Ministers vowed last night to fight to preserve Britain’s more flexible working hours after an outcry from employers over the move by the European Parliament’s employment committee to scrap the UK opt-out, which dates from 1993.

The latest twist in the long battle over the working time directive means that the full Parliament will vote on it next month in a direct challenge to a compromise agreement hammered out by EU member states earlier this year.

Under current arrangements, British workers can decide to work up to 78 hours in any one week in busy periods, under EU law, rather than be limited to a 48-hour maximum. Such flexibility is retained under a deal by which the Government has agreed to give temporary workers full employment rights after 12 weeks in a job. The whole package is now at risk because the European Parliament must sign it.

Besides ending the working time opt-out, the MEPs’ committee voted to include all on-call time in an employee’s working hours. If confirmed by an absolute majority of MEPs in the full European Parliament on December 17, this would be another blow for ministers who had negotiated to include only “active” on-call time in calculating working hours, to save hospitals from having to hire more doctors.

Lord Mandelson, the Business Secretary, said: “The decision by the employment committee is not surprising in the least. We will continue to stand firm to protect the opt-out to the working time directive’s 48-hour maximum working week, which is essential to Britain’s labour market flexibility, which has helped to create an extra three million jobs over the past decade.

“People must remain free to earn overtime if they wish and businesses must have the flexibility to cope during busy times. To lose the ability to opt-out will mean workers cannot boost their earning potential when some are already struggling with high food and energy prices.”

Alistair Tebbit, of the Institute of Directors, said: “MEPs have made a big mistake by voting in favour for abolition of the opt-out . . . As the EU enters recession, employers need more flexibility, not less.”

Stephen Hughes, a Labour MEP and Socialist Group spokesman on employment, who voted to end the opt-out, said: “It has always been the position of the Socialist Group to be against the opt-out on working time because of concerns about health and safety.”

A new compromise looks unlikely since the European Commission has supported the European Council [of ministers’] proposals for the opt-out to continue. The scene is set for a stand-off between MEPs and ministers if the European Parliament agrees with its employment committee next month.

The opt-out negotiated by the Conservatives in 1993 has been defended by Mr Brown against unions’ attacks.

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