The study found that while child mortality fell by 11%, from 93 to 83 deaths per 1000 live births during the 1990s—1 in every 12 children dies before age 5 from preventable diseases.

The 102 page study—an update of a 1990 report covering child heath, education, nutrition, and protection in nearly 150 countries—concluded that healthy and educated children are vital to economic development and urged governments to invest more in future generations.

"National leaders must act on the past decade's most important lesson: that investing in children from the earliest years is neither a charitable gesture nor an extravagance, but is rather the best way to ensure long-term development," the report said.

The report was compiled for the UN General Assembly Special Session on Children, to be held next week in New York and at which more than 70 world leaders and 170 national delegations are due to set targets on the survival, development, and protection of young people.

Billed by the United Nations as "the most comprehensive study ever released on the condition of children," the study found that although malnutrition had been reduced by half globally among children aged under 5, child mortality in Africa and South Asia was extremely high with malnutrition playing a role in half of such deaths in those regions.

The report said that more than 10.5 million children die a year, 150 million are malnourished, and 120 million—mainly girls—never go to school. It criticised governments, both in developing and industrialised countries.

It quoted a 1998 study by the Rand Corporation concluding that for every $1 (69p; €1) invested in the physical and cognitive development of infants and young children there is a $7 return—mainly from future savings on costs, such as health care, remedial education, unemployment, and crime. It cited other studies also showing large scale returns on investment in health and education.

Last month the United Nations Children's Fund (Unicef) said that it was on track to eliminate tetanus, a major killer of infants in the developing world, in the next three years. In 2001, it said that vaccination and other programmes had helped to avert 15 000 deaths from the disease among newborn infants. Unlike smallpox and poliomyelitis, complete eradication of tetanus is not possible as the spores survive for a long time outside the human body, but it can be eliminated through vaccination of infants, children, and women at risk and through the promotion of safe and clean delivery practices.