His family remembers him as a global statesman, one who was a deeply committed internationalist who fought throughout his life for a fairer and more peaceful world.
In a statement following the event, UN spokesperson Fred Eckhard said that Annan "believes that the United Nations can not condone any persecution of, or discrimination against, people on any grounds, and recalls Article 2 of the Universal Declaration of Human Rights, which says that 'Everyone is entitled to all the rights and freedoms set forth in this Declaration, without distinction of any kind'".
Director General of the The Norwegian Nobel Committee, Gunnar Berge (left), awards UN Secretary General Kofi Annan with the 2001 Nobel Peace Prize in Oslo on December 10, 2001.
He later served as the United Nations special envoy for Syria, leading efforts to find a peaceful solution to the conflict.
"His absence will be keenly felt, and we offer our deepest condolences to his wife and family".
Also, former Vice-President Atiku Abubakar described Mr Annan as a man whose "contributions to humanity will not be forgotten".
From 1954 to 1957, Kofi Annan attended the elite Mfantsipim school in Cape Coast and then studied economics at the Kumasi College of Science and Technology, now the Kwame Nkrumah University of Science and Technology from 1958. A year later he established the Kofi Annan Foundation in the Swiss city.
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The longtime United Nations diplomat was the first black African to serve as secretary-general and was lauded for his humanitarian efforts.
Kofi Annan was the first black African to lead the United Nations and the first to come from the UN's own ranks.
Annan was known to diplomats as a lifer - a career diplomat at the United Nations who remained active after his two terms.
"His death is a loss not only to Africa but to the rest of the world".
"The world has lost a great humanitarian, leader, and self proclaimed "stubborn optimist".
Ghana's President Nana Akufo-Addo on Saturday hailed Mr Annan as a consummate worldwide diplomat who had brought vast pride to his country.
Annan's death, following a short illness, was announced earlier on Saturday.
UN High Commissioner for Human Rights, Zeid Ra'ad al-Hussein, paid tribute to Annan as "humanity's best example, the epitome, of human decency and grace".
The ANC called Annan "an eminent and distinguished son of Africa and a great friend of the people of South Africa who played an immeasurable role in shaping the global agenda in favour of the people of the developing South". "Annan showed that one can be a great humanitarian and a strong leader at the same time", North Atlantic Treaty Organisation chief Jens Stoltenberg, another former Norwegian prime minister, said in a statement.