The death of Nelson Mandela is not just a loss for South Africa. It is a loss for people all over the world who are fighting for freedom, for justice and for an end to discrimination.
"As a world leader who refused to accept injustice, Nelson Mandela's courage helped change our entire world," said Salil Shetty, Secretary General of Amnesty International. "His death leaves a massive hole, not just in South Africa but around the world.
"Nelson Mandela's commitment to human rights was epitomised by his unswerving resolve to stamp out racial inequality during apartheid, followed by his vital work in combating HIV/AIDS in South Africa. His legacy across Africa, and the world, will stand for generations."
Nelson Mandela's life of political struggle and self-sacrifice stands as an example to millions around the globe. His grace under pressure, his courage and integrity and his commitment to healing and forgiveness over revenge and hatred was remarkable.
"One was struck by this man as being somebody quite outstanding," said Louis Blom-Cooper, who was involved in the foundation of Amnesty International in the early 1960s and was an observer at the long-running trial of Nelson Mandela and other anti-apartheid leaders on treason charges prior to their acquittal in March 1961.
"Literally, to face him and hear him speak, one felt one was in the presence of a very substantial individual who one day would become a very prominent citizen of South Africa.
"He had a very appealing face and when he spoke to you, you felt the most important person at that moment was yourself and not him."
In the years following his presidency, Nelson Mandela's outspoken and determined advocacy on behalf of the millions of people living with HIV, particularly in sub-Saharan Africa including South Africa, showed his passion for upholding human dignity, the right to equality and access to justice had not dimmed with time.
His insistence that these were human rights issues helped to ensure that the circumstances of people living with HIV remained an urgent global concern.
In November 2006, Amnesty International declared Nelson Mandela an 'Ambassador of Conscience' in recognition of his work over many years of speaking out against human rights abuses not just in South Africa but around the world.
Accepting the award, Mandela said: "Like Amnesty International, I have been struggling for justice and human rights, for long years. I have retired from public life now. But as long as injustice and inequality persist in our world, none of us can truly rest. We must become stronger still.
"Through the work of the Nelson Mandela Foundation, the Nelson Mandela Children's Fund, and The Mandela Rhodes Foundation, I am continuing my struggle for human rights."
On the same occasion the organisation presented Mandela and the Nelson Mandela Foundation with five volumes of public reports and campaigns issued by Amnesty International between the 1960s and 1994 on human rights abuses in South Africa.
In accepting the Ambassador of Conscience Award, Mandela graciously acknowledged Amnesty International's contribution in the fight for human rights.
Nelson Mandela was a victim of great injustice, tried and sentenced under a system of apartheid founded on racism and denied a fair trial.
As Amnesty International noted in its 1978 report on political imprisonment in South Africa: "While apartheid remains there can be no structure which conforms with and guarantees recognised standards of human rights."
"Nelson Mandela was a political prisoner, detained also for his conscience. He was a man who understood how exclusion of groups destroys the social fabric of a country by creating a politics of inequality. The human rights movement around the world owes Nelson Mandela a debt of gratitude. All of us who admired him must carry on his struggle," said Salil Shetty.
This article was reproduced with the kind co-operation of Amnesty Interational. Visit the Amnesty website to find out more about their current campaigns to promote justice and tackle abuse around the world.