This photo taken on May 26, 2004 shows US President George W. Bush (R) shaking hands with Gabon President Omar Bongo Ondimba as the meet privately in the Oval Office of the White House in Washington, DC. Africa's longest-serving ruler, Gabon President Omar Bongo Ondimba, who was being treated for an illness in a Spanish clinic, has died aged 73, a French government source said on June 7, 2009.