Reducing child mortality in India and China, the world's two most populous countries, poses the biggest challenge.

In 2006, India and China accounted for nearly a third of all child deaths worldwide, the UN agency said.

In India alone, child deaths were 2.1 million while in China, they were 415,000.

While noting that health services had improved impressively with the rapid economic growth in both India and China, more needs to be done in both countries and the entire Asia-Pacific region, Unicef said in its State of Asia-Pacific's Children 2008 report.

The report pointed out that public health expenditures in the region averaged 1.9 percent of its gross domestic product (GDP), well below the world average on 5.1 percent. In South Asia, health spending was 1.1 percent of GDP.

The Unicef report noted that as more of the region's health services are privatized, governments' health budgets have fallen, resulting in declining public facilities for the poor.

`The divide between rich and poor is rising at a troubling rate within subregions of Asia-Pacific, leaving vast numbers of mothers and children at risk of increasing relative poverty and continued exclusion from quality primary health-care services,' the report said.

In China, most child deaths occur within the first week of life, largely because of a lack of obstetric services.

In India, one out of every three women is underweight, putting them at risk of having babies with low birth weights and these babies are 20 times more likely to die in infancy than healthy babies.

South Asia is the only subregion in the world where female life expectancy is lower than male life expectancy.

`Unless discrimination against women and girls is addressed as part of overall strategies to improve child and maternal health, high rates of maternal and child mortality will remain stubbornly entrenched,' the report concluded.

Without improved health care, 13 Asia-Pacific countries would struggle to reduce their child mortality rates by two-thirds by 2015, it warned.

Other UN millenium development goals include eradicating extreme hunger and poverty, achieving universal primary education, promoting gender equality, combating disease and ensuring environmental sustainability.