London Mayor Boris Johnson today slammed 'barmy' health and safety rules after a couple were threatened with being referred to social services for letting their children cycle to school.

Oliver and Gillian Schonrock let their son and daughter, five and eight respectively, make the one-mile trip from their home on their own.

They say it helps to teach the youngsters independence, self-confidence and responsibility.

But other parents and teachers at £12,000-a-year Alleyn's Junior School in Dulwich, south east London, are said to think the practice is irresponsible and dangerous.

Headteacher Mark O'Donnell has met with Mr and Mrs Schonrock and told them the school is under an obligation to consider the children's safety and has a legal responsibility to notify the council if they fear it is being put at risk.