"This is a matter of trust ... it (climate-finance commitment) must be fulfilled," said Mary Robinson, former president of Ireland and chair of the Elders, during an exclusive interview with CGTN. In 2009, at a United Nations climate summit in Copenhagen, rich nations made a significant pledge to channel $100 billion a year to less wealthy nations by 2020 to help them adapt to climate change and mitigate further rises in temperature. But till now, the pledge has not been fulfilled yet.