Obama hits out at leaders who don't tolerate dissent from own people

There are too many leaders who claim solidarity with Madiba's struggle for freedom, but do not tolerate dissent from their own people, US president Barack Obama said on Tuesday.

Obama also said, "...there are too many of us who stand on the sidelines, comfortable in complacency or cynicism when our voices must be heard."

The US President said, "The questions we face today - how to promote equality and justice; to uphold freedom and human rights; to end conflict and sectarian war - do not have easy answers."

"We can choose a world defined not by conflict, but by peace and justice and opportunity," added Obama.

"We will never see the likes of Nelson Mandela again.  But let me say to the young people of Africa, and young people around the world - you can make his (Mandela) life's work your own."

"Mandela taught us the power of action and the power of ideals, the importance of reasons and arguments. He understood the ideals could not be contained within prison walls," said Obama, to loud cheers from the crowd.

"He used decades of prison to sharpen his argument...he learnt the language and customs of his oppressors."

Obama said the world thanked South Africa for sharing Mandela.

"It is an honour to be with you today, to celebrate a life like no other," he said.

"People of every walk of life, the world thanks you for sharing Mandela with us. His struggle was your struggle. His triumph was your triumph."

Mandela was the last great liberator of the 20th century.

He was committed to democracy and rule of law, and received the adoration he deserved, said Obama.

Madiba could admit to imperfection and showed humility.

"We loved him so....He was a man of flesh and blood, a son and a husband...that's why we learnt so much from him."

He earned his place in history through the struggle, said Obama.

The crowd listened tentatively to US president Barack Obama's tribute to former president Nelson Mandela at FNB Stadium.

Obama, wearing a dark suit with a blue tie, quoted from Mandela's Rivonia Treason Trial speech.

When he said, "this is an ideal for which I am prepared to die", the crowd erupted with cheers and applause.

"Amandla Nelson Mandela," said Obama.

Most people stood, huddled under colourful umbrellas, to get a better look at the US head of state as he gave a passionate speech about Mandela.

The crowd cheered in appreciation of what he was saying.

FNB Stadium was the site of Mandela's first speech inland shortly after his release from prison in 1990.

Mandela died at his home in Houghton, Johannesburg, on Thursday, at the age of 95. He will be buried in Qunu, in the Eastern Cape, on Sunday.