Youssou Ndour: King of African pop returns with new album ‘History’

He's a first-class singer and Grammy Award-winning musician but also a politician and the former culture minister for Senegal. The king of African pop has become a worldwide ambassador for his continent's music. Youssou Ndour speaks to Eve Jackson about his new album "History", what his 1994 duet with Neneh Cherry "7 seconds" changed for him, and what he believes is the biggest challenge for Senegal's future.