Substantial reductions in the number of children suffering from mental disorders will not be seen for around 10 years, a mental health charity said today.

The warning from the charity, Young Minds, came after government figures revealed that the prevalence of mental disorders among children and teenagers had not fallen between 1999 and 2004.

The survey by the national statistics office showed that one in 10 children aged five to 16 in England, Scotland and Wales had a mental disorder last year.

Dinah Morley, deputy director of Young Minds, said the level of mental disorders among children should start to fall in 10 years' time.

Ms Morley said that, while more funding in child and adolescent mental health services was still required, government investment in parenting support services such as Sure Start would pay dividends in terms of children's longer-term psychological wellbeing.

"Parenting classes should hopefully improve early attachment between parent and child, which should reduce mental health problems such as conduct disorders," she said.

Ms Morley said the survey highlighted the role played by social deprivation and family breakdown on child mental health.

One in five children and young people whose parents are both unemployed suffer a clinically recognised mental disorder, compared to 8% of children from families in which both parents work.

The survey of 7,977 children also found that mental disorders were more than three times as common among children from families with a weekly income of less than £100 (16%) than in those with a weekly income of £600 or more (5%). Children in low income, high unemployment areas were twice as likely to have mental illnesses (15%) as those in affluent areas (7%).

Disorders were twice as common among children of lone parents (16%) than those from two parent families (8%). Rates were also substantially higher among children in stepfamilies (14%) than in those with no stepsiblings. Autistic children bucked the trend, tending to have more highly-qualified parents than others.

Overall, the survey by the Department of Health and the Scottish Executive showed 4% of children and young people had emotional disorders such as anxiety or depression. Six percent had conduct disorders, and 2% suffered from hyperkinetic disorders - also known as attention deficit hyperactivity disorder (ADHD).

The survey found that 1% had a less common disorder such as autism, tics or eating disorders while some (2%) had more than one type of disorder.