World remembers 'liberator' Mandela
Barack Obama has led tributes to Nelson Mandela, urging the world to build on his legacy and tackle poverty and inequality.
The US president spoke of the "heroic" life of the South African anti-apartheid leader describing him as the "last great liberator of the 20th century" as he addressed thousands gathered for the memorial service to Mr Mandela in the rain-soaked FNB Stadium in Soweto.
Mr Obama compared Mr Mandela's actions to those of Gandhi, Abraham Lincoln and US civil rights leader Martin Luther King but also warned against viewing Mr Mandela as detached from normal life.
"He was not a bust made of marble, he was a man made of flesh and blood," Mr Obama told the crowds in the stadium including leaders from more than 90 countries.
Mr Obama singled out world leaders who have publicly welcomed gains made by Mr Mandela but resist reforms to tackle inequality and injustice.
"Around the world today we still see children suffering from hunger and disease and we still still see run down schools and we see young people without prospects for the future," he said.
"Around the world today men and women are still imprisoned for their political beliefs and are still persecuted for what they look like and how they worship and who they are, that is happening today.
"There are too many people who happily embrace Madiba's (Mandela's) legacy of racial reconciliation but passionately resist even modest reforms that would challenge chronic poverty and growing inequality.
"There are too many leaders who claim solidarity with Madiba's struggle for freedom but do not tolerate dissent from their own people.
"There are too many of us on the sidelines comfortable in complacency or cynicism."
Mr Obama warned against viewing Mr Mandela as "detached" from normal life.
"It was precisely because he could admit to imperfection, because he was so full of good humour, even mischief despite the heavy burdens that he carried, that we loved him so," he said.
"He was not a bust made of marble, he was a man of flesh and blood, a son and a husband, a father and a friend, that is why we have learned so much from him and that is why we can learn from him still.
"Nothing he achieved was inevitable, in the arc of his life, we see a man who earned his place in history through struggle and shrewdness and persistence and faith."
Mr Obama's speech came after he shook hands in the stadium with Cuban president Raul Castro, the first such greeting in public involving a president of the US since the Cuban revolution. The former US president Bill Clinton reportedly shook hands in private with Raul's brother Fidel behind closed doors at a UN lunch in 2000.
The US president also shook hands and kissed Brazilian president Dilma Rousseff on both cheeks. The gesture came after she cancelled a recent trip to the US, amid anger over revelations that the NSA had eavesdropped on her phone calls.
During the service in the two-thirds filled stadium, boos were heard for the current South African president Jacob Zuma and the former US president George W Bush. But there were cheers for Mr Obama - and for the Zimbabwean president Robert Mugabe.
Those attending included Prime Minister David Cameron and his three surviving predecessors, Sir John Major, Tony Blair and Gordon Brown.
Also seen arriving at the service were supermodel Naomi Campbell, rock star Bono, former South African president FW De Klerk, Mr Clinton and his wife ex-US secretary of state Hillary Clinton, former French president Nicolas Sarkozy and the current French president Francois Hollande.
Mr Mandela, described at one time as the world's most famous political prisoner, was released after 27 years in jail in 1990 and went on to become South Africa's first black president. He died last Thursday aged 95 years old.
The service, marked by heavy rain, heard from Andrew Mlangeni, a former prisoner on Robben Island with Mr Mandela, who spoke of the "outpouring of love" following his death.
"Madiba is looking down on us. There is no doubt he is smiling and he watches his beloved country, men and women, unite to celebrate his life and legacy," he said.
UN secretary-general Ban Ki-moon told the service: "South Africa has lost a hero, we have lost a father and the world has lost a beloved friend and mentor.
"Nelson Mandela was more than one of the greatest leaders of our time, he was one of our greatest teachers. He taught by example, he sacrificed so much and was willing to give up everything for freedom, equality and justice.
"His compassion stands out most."
Mr Zuma, addressing the service, said: "Today Madiba is no more. He leaves behind a nation that loves him dearly. He leaves a continent that is truly proud to call him an African.
"He leaves the people of the world who embraced him as their own... icon. Most importantly, he leaves behind a deeply entrenched legacy of freedom, human rights and democracy in our country.
"In his honour we commit ourselves to continue building a nation based on the democratic values of human dignity, equality and freedom. United in our diversity we will continue to build a nation free of poverty, hunger, homelessness and inequality."
Speaking to the BBC, Mr Blair said the service was "extraordinary".
"He was so good with everyone, so easy with everyone, he was very determined, not to turn into, as Barack Obama said earlier, a sort of 'marble bust' , a sort of remote figure. He was very human and great fun," Mr Blair said.
"He was always reaching out to people, always trying to reconcile them and bringing people together and he did it in a way where there was something quite transcendent about it," he said.
"It was uncanny, his ability to reach people, not just on an emotional but almost on a spiritual level."
Mr Mandela's body will lie in state at South Africa's seat of government, the Union Buildings in Pretoria, until he is laid to rest in a state funeral at his home town of Qunu in the Eastern Cape on Sunday.
The Prince of Wales will be among a smaller number of dignitaries travelling to the remote rural location for that service.
Model Naomi Campbell said she will be "eternally grateful" to have known Mr Mandela.
She told ITV News: "It's been an amazing service and everyone has come together. Only Mr Mandela, Madiba, Tata, could bring everyone together like this.
"I got to know him for 20 years and it's an honour and a blessing and I'm truly in awe and will always be eternally grateful.
"Sharing, forgiving and a lot of things. he means a lot to me and I have a lot of wonderful memories... He is someone that I will treasure in my heart for the rest of my life.
"It's about celebrating his life, we feel sad and grieve but it's not all I think he would want. He wants us to celebrate his life and his legacy."