Former United Nations Secretary General and Nobel laureate Kofi Annan has died, his foundation announced on Saturday. Annan was 80 and had won the Nobel Peace Prize in 2001 for humanitarian work.

“He passed away after a short illness,” the Kofi Annan Foundation said in a statement on Twitter. He is survived by his wife and three children.

Ghana’s Annan was the UN’s seventh secretary general and served from 1997 to 2006. At his initiative, UN peacekeeping was strengthened in ways that enabled the United Nations to cope with a rapid rise in the number of operations and personnel, according to the UN website. As secretary general, one of Annan’s main priorities was to implement reforms to revitalise the UN and make the international system more effective.

Annan was a constant advocate for human rights, the rule of law, the Millennium Development Goals, and Africa. “During his distinguished career and leadership of the United Nations, he was an ardent champion of peace, sustainable development, human rights and the rule of law,” the Kofi Annan Foundation said.

Annan joined the UN system in 1962 as an administrative and budget officer with the World Health Organization in Geneva. He served with the Economic Commission for Africa in Ethiopia’s Addis Ababa, the UN Emergency Force in Egypt’s Ismailia, the United Nations High Commissioner for Refugees in Geneva, and in several senior positions in New York. Before becoming secretary general, Annan was the under-secretary-general for peacekeeping.

‘True son of Africa’: Several leaders pay their tributes

Many prominent leaders condoled Annan’s death.

UN Secretary General Antonio Guterres said that Annan, in many ways, was the United Nations. “Kofi Annan was a guiding force for good,” Guterres said in a statement. “He rose through the ranks to lead the organisation into the new millennium with matchless dignity and determination.”

Congress MP Shashi Tharoor, who worked at the UN, said that Annan was one of the greatest secretary generals. “Kofi Annan was a proud son of Africa, a great admirer of India, a voice of the developing world, a paragon of internationalism & an exemplar of humanity,” tweeted Tharoor. “The UN was fortunate to have been led by him at a pivotal moment in world history. He remains one of its greatest SecGens.”

President of the World Economic Forum Borge Brende described Annan as a global statesman who fought throughout his life for a fairer and more peaceful world. “A true son of Africa that always reached out and touched people with his deep compassion and empathy,” he tweeted.

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