The review of existing scientific literature was commissioned by the British Government and published yesterday.

Parents were urged to limit mobile phone use by children because of potential dangers.

Campaigners fear users risk cancer, brain damage, Alzheimer's disease, sleeping disorders and memory loss because of radiation emitted by handsets into the head.

Those concerns have been heightened by several scientific studies.

The government report says problems may be hidden because mobiles have been used widely for only a few years.

"We cannot be sure what will be found and the possibility of an effect still remains," said team head Professor Anthony Swerdlow, of the Institute of Cancer Research.

Spokesman for the National Radiological Protection Board Dr Mike Clarke advised caution.

The report found no definitive link to health problems from mobile phones but called for more research.