As the 20th century came to a close, Gaddafi increasingly rejected Arab nationalism, frustrated by the failure of his Pan-Arab ideals; instead he turned to Pan-Africanism, emphasising Libya's African identity. From 1997 to 2000, Libya initiated cooperative agreements or bilateral aid arrangements with 10 African states, and in 1999 joined the Community of Sahel-Saharan States. In June 1999, Gaddafi visited Mandela in South Africa, and the following month attended the OAU summit in Algiers, calling for greater political and economic integration across the continent and advocating the foundation of a United States of Africa. He became one of the founders of the African Union (AU), initiated in July 2002 to replace the OAU; at the opening ceremonies, he proclaimed that African states should reject conditional aid from the developed world, a direct contrast to the message of South African President Thabo Mbeki. At the third AU summit, held in Libya in July 2005, he called for a greater level of integration, advocating a single AU passport, a common defence system and a single currency, utilising the slogan: "The United States of Africa is the hope." In June 2005, Libya joined the Common Market for Eastern and Southern Africa (COMESA), and in August 2008 Gaddafi was proclaimed "King of Kings" by an assembled committee of traditional African leaders. On 1 February 2009, his "coronation ceremony" was held in Addis Ababa, Ethiopia, coinciding with Gaddafi's election as AU chairman for a year.