No country offers a child both the chance of a healthy upbringing and an environment fit for their future, the World Health Organization (WHO) says.
Experts say climate change and harmful advertising encouraging fast-food consumption and under-age drinking are putting children at risk.
The UK was ranked among the top 10 countries in the world for the overall health and wellbeing of children.
However, it fell behind in safeguarding the environment for their future.
The report by the WHO, the United Nations Children’s Fund (Unicef) and the Lancet Commission, ranked 180 countries on the likelihood of a child being able to “flourish”, focusing on health and wellbeing factors such as education, nutrition and child mortality.
Read more on the BBC Website