LONDON: Contraception advice is crucial to poor countries' battle with climate change, and policy makers are failing their people if they continue to shy away from the issue, a leading family planning expert said on Friday.

Leo Bryant, a lead researcher on a World Health Organization study on population growth and climate change, said the stigma attached to birth control was hindering vital progress.

"We are certainly not advocating that governments should start telling people how many children they can have," said Bryant, who wrote a commentary in the Lancet medical journal on Friday.