Following the publication of two critical reports, David Blunkett has announced that prisons will now hold juvenile girls and adults in separate units.

Female prisoners under the age of 18 will be held away from the main adult populations in women's prisons, the home secretary said.

His move comes as three independent watchdogs issued a joint warning that there were "significant weaknesses" in provisions for child prisoners in England and Wales.

However, prisons inspector Anne Owers, Ofsted and the Youth Justice Board accepted that the system had improved over recent years.

Owers said that girls aged 15 to 18, often held in small numbers in adult prisons, had low levels of self-esteem.

The youth justice system was "failing this vulnerable and damaged group of young women", Owers said in a joint statement with Ofsted chief David Bell.

The Prison Service currently holds 86 girls under the age of 18, compared to 76 last June.  In contrast, there are 2,612 males under 18 in prisons in England and Wales.

Quality

Owers said the system was "undoubtedly providing a better deal for some very damaged young people" but problems remained in areas such as the distance from home and the variation in the quality and quantity of education and training.

There should also be "much greater investment" in the young people when they are released, added Owers.

"Around 90 per cent of young people said that they wanted to stop offending but the Ofsted report vividly documents the lack of support available to sustain the work done in prison," she added.

And the Ofsted chief inspector added that the report on educational experiences of girls in prison "makes sobering reading".

"It demonstrates again that for too many young people, low attainment at school is related to subsequent criminal behaviour," he said.

"Too many of the girls seen by inspectors report highly negative experiences during their time in statutory schooling.

"The most pressing task is to ensure better continuity in education when girls leave custody.

"Too often the gains made in prison are not sustained outside, a serious concern if education is to be of lasting value in helping young women rebuild their lives."

Custody

Owers and Bell also issued a joint call to end the practice of holding girls in Prison Service custody.

Responding to the reports, Juliet Lyon of the Prison Reform Trust called for more support for offenders when they are released.

"Almost all the young men and women interviewed in these surveys wanted to stop offending. The tragedy is that they have so little support on release to help them realise this ambition," she said.

"Trying to turn prisons into suitable environments for vulnerable young women is a questionable use of scarce resources.

"Given that very few young women commit crime and that prisons are not geared up to work effectively with them, surely it should be possible to create small secure support and supervision centres near to their homes connected to the mental health, drug treatment, housing, employment and social services that they so badly need."