More than 12,000 children in the West Midlands - and as many as 963,000 in Britain - are living with domestic violence, physical or sexual abuse, according to a report published today.

Statistics published in a joint report by Unicef, the United Nations and the Body Shop International, found up to 275 million children are victims of violence in their own homes, across the world.

The report, Behind Closed Doors: The Impact of Domestic Violence on Children, also reveals one in 14 children in the UK receive poor exam results as a result of physical, sexual or verbal abuse, while 40 per cent have lower reading abilities than peers from non-violent homes.

In the West Midlands, 12,324 children were helped by volunteers at Women's Aid refuges, but the authors fear this may only be the tip of the iceberg, as many cases still go unreported.

While the effect of violence on women is well-documented, little has been done to establish its impact on children and teenagers, who can go on to suffer low self-esteem, aggression, and behavioural problems.

Dr Amaya Gillespie, director of the United Nations Secretary General's Study on Violence, said: "We are just beginning to develop a clearer global picture of the problem and are in a position to call for action by governments and communities to stop the exposure of children to domestic violence."

Anita Roddick, of the Body Shop, said the statistics were "appalling" and was shocked that many more cases go unreported. She said: "It's likely that there are many more victims out there completely off the radar.

"Domestic violence is one of the biggest human rights challenges of our time. It is a global phenomenon of epic proportions that knows no geographical boundaries.

"If we don't take action now, then, without a doubt, society will continue to suffer as these young victims become adults." Home Office Minister Baroness Scotland said: "Every child has the right to live without the fear of violence.

"These findings demonstrate the need for us all to take responsibility for bringing about change and for keeping our friends and communities safe from a crime which devastates families and ruins lives."