Former children's commissioner for England Sir Al Aynsley-Green has accused the Government of having "short-term, inconsistent and untrustworthy" policies that are letting down young people across the country.
Professor Aynsley-Green is calling for a "wholesale cultural change of attitude" towards children, and says if Government continues to fail them, responsibility must fall on local communities.
He will make his plea at a conference in London on Thursday which will examine the treatment of children in their first three years of life.
Professor Aynsley-Green, also a past president of the British Medical Association, says British children have some of the worst outcomes for health, education, social care, youth justice and poverty in the developed world, and believes urgent action is needed to improve their lives.
Calling for a bottom-up, community-based change, he will say: "Children are our most precious resource, and we need healthy, educated, creative and resilient children now, with the life skills as adults to support an ever-ageing population."
He will add: "Whilst we have amazing children and young people, nonetheless far too many are being failed by political and public attitudes to the importance of children, with Government policies being short-term, inconsistent and untrustworthy, and a failure of effective advocacy to promote the needs and best interests of children and families.
"We need a wholesale cultural change of attitude to the importance of children in this country across communities, organisations and decision makers and to take best practice from other countries such as Finland, Holland and Canada.
"If Government isn't prepared to put children at the heart of a coherent joined-up policy, then we need a momentum to build local communities with resilient children at their hearts."
Neil Leitch, chief executive of the early years organisation Pre-school Learning Alliance, also advocates a child-focused early years policy.
Mr Leitch will say: "Study upon study has shown how important it is to give children a firm foundation from which to start their lives.
"Early years providers - working in partnership with parents and families - play a pivotal role in helping support children to grow up strong, confident, and resilient, but equally important is a continued push for Government policy that has the needs of the child at its core."
The conference is being hosted by charity What About The Children?.