A climate plan by the city of Brussels has pledged to plant a tree for every baby born within the Belgian capital.
The city says that means about 2,000 trees will be planted each year.
The project is designed to mitigate the effect of CO2 emissions, help with reforestation and boost biodiversity.
Officials told Euronews the trees would be planted in Senegal.
The city is also trying to reduce greenhouse gas emissions, increase the uses of renewables and improve energy efficiency.