In his opening speech, Portuguese President Marcelo Rebelo de Sousa praised Portuguese government's action for a sustainable environment and the role of the UN Secretary-General Antonio Guterres in combating climate change.
"Lisbon opens the way, Portugal follows the way, Europe supports the way, Antonio Guterres takes the universal witness further along the way. We are together and we will win," exclaimed Rebelo de Sousa.
The UN chief and Portuguese Prime Minister Antonio Costa also attended the opening ceremony.
According to the European Commission, the European Green Capital Award is given annually with the aim of recognizing the efforts of cities with a plan to become environmentally friendly and involving their people in environmental, social and economic sustainability.