The conclusion was drawn at a meeting held by the French government in Paris on July 8 to study actions taken to implement the Paris agreement in order to reduce health risks linked to climate change.
Experts noted that climate change was already causing tens of thousands of deaths every year. This is in addition to 7 million deaths caused by air pollution, a release by WHO said.
The biggest burden of the additional fatalities will be borne by children, women, older people and the poor, further widening the existing health inequalities.
WHO has already published profiles on 40 countries.
During the conference, benefits of switching to cleaner energy sources were also discussed.
The participants also asked countries to develop a new approach to link investment in mitigating climate change with the expenditure on related healthcare costs, the release added.