Former prime minister Tony Blair said Nelson Mandela was a "great man" who had made racism "not just immoral but stupid".
Mr Blair said: "Through his leadership, he guided the world into a new era of politics in which black and white, developing and developed, north and south, despite all the huge differences in wealth and opportunity, stood for the first time together on equal terms.
"Through his dignity, grace and the quality of his forgiveness, he made racism everywhere not just immoral but stupid; something not only to be disagreed with, but to be despised. In its place he put the inalienable right of all humankind to be free and to be equal."
Six-year-old Emma Williams was invited to sit on Nelson Mandela's lap when he visited Wales in June 1998. Now 22, she speaks to ITV News.
Nelson Mandela touched aspects of British public life in a way that very few other international figures have managed.