More people are now working longer hours than 10 years ago, according to new research by the trade unions.

A UK opt-out of the EU's working time directive puts Britain top of the European long hours league, a situation TUC chief John Monks brands a "national disgrace".

"Britain's long hours culture is a national disgrace. It leads to stress, ill health and family strains. But even worse it's an indictment on how badly we manage work in the UK," said Monks.

With a review of the legislation in 2003 almost certain to lead to tougher regulations for the UK and with stress claims spiralling, a twelve-fold increase in the last 12 months, the TUC is calling on employers to "work-smart" and organise the working week more effectively.

"Half the country is caught in a vicious circle of low pay, low productivity and long hours, with the other half trapped in their offices and battling ever growing in-trays. Other countries produce more, earn more and work far shorter hours. We should, and can, do the same, if employers, unions and government work together," said Monks.

But the TUC's call is rejected by bosses and the CBI is set to "vigorously defend the right of employees to choose the number of extra hours they work".

The CBI believes that "workers want the right to make their own decisions about working extra hours" and that the concentration of long hours among managers reflects commitment to the job.

"Managerial workers often work longer hours because they want to. Operational staff often work longer hours because they are paid for it. Neither group will thank the government for intervening. They don't want a nanny state," said CBI deputy director-general, John Cridland. "There may be a culture of working long hours in some firms, but it is wrong for the TUC to describe this as a 'national disgrace'. Reducing long hours should be a matter of individual choice."

The TUC report finds that 16 per cent of the workforce, nearly four million employees, are now working over 48 hours a week and nearly 1.25 million are working over 55 hours.

The average working week is 43.6 hours in the UK compared to an EU average of 40.3 hours.

And the research points to a new class divide with managerial and professional employees the most likely to be working long hours - 2.25 million are working in excess of 48 hours and the number of male managers working more than 48 hours is nearly three times the national average.

The report follows figures published at the weekend revealing that work-related stress litigation had "soared" with a twelve-fold increase on last year.