His predecessor as secretary-general, Kofi Annan, is chairman of The Elders. He said yesterday in announcing the appointment that Ban "will bring a unique and valuable perspective based on his record of global leadership and understanding of geopolitics."
Ex-Norwegian Prime Minister Gro Harlem Brundtland, deputy chair of the group, said Ban will take on issues that he championed as secretary-general climate action, gender equality and UN action to combat poverty.
Ban was secretary-general from 2007 through 2016. He said: "The Elders and the United Nations share the same values of justice, solidarity and a determination to fight for peace and human rights.