Ministerial attempts to encourage a better work-life balance are being hit by the government's own EU working time directive opt out, the TUC has said.

Publishing a new report with the Working Families charity on Friday, the trade union group claimed that the exemption from the maximum 48 hour working week is damaging families.

The "More time for families" study found that despite the directive more people are working excessive hours than in 1992.

As a result parents are unable to spend the quality time with their children the government has identified as crucial to encouraging good behaviour and high achievement in the young, the groups said.

A Working Families survey discovered that 44 per cent of respondents in full-time employment regularly have to work more than 48 hours per week.

Labour has signed up to this maximum in principle but insists on allowing it to be broken if both the employer and employee agree.

But the survey found that nine out of ten parents believe long hours harm family life.

And an analysis in the report of tribunal appeals under the directive concluded firms are still not enforcing the EU rules.

TUC general secretary Brendan Barber said scrapping the opt out would be a vote winner.

"Excessive hours are bad news for everyone and especially damaging for workers with families," he said.

"Whilst ministers remain wedded to the idea of maintaining the UK's individual opt-out, the children of long hours parents will go on suffering.

"A clamp down on employers abusing working time rules and the removal of the opt-out would prove very popular with working parents."