Tributes were paid to former UN secretary general Kofi Annan as he was laid to rest in his native Ghana on Thursday, with calls to keep alive the legacy of a "stubborn optimist" to create a better, more peaceful world.

His widow Nane Maria led hundreds of mourners, including world leaders past and present, traditional rulers and global royalty, and called her husband an "extraordinary" person who had a "joy of life".

"My love, you are now back home where you started your long journey. But may your wisdom and compassion continue to guide us, wherever we are," she told his state funeral in the capital, Accra.

Opera singer Barbara Hendricks, a UN refugee council goodwill ambassador who sang at Annan's Nobel ceremony, performed the civil rights anthem "Oh, Freedom" at the funeral of Christian prayers and song.

Annan led the UN from 1997 to 2006 and was the first from sub-Saharan Africa to do so. He died on August 18 aged 80 at his home in Switzerland after a short illness.

Thousands of people have this week filed past his coffin this week during three days of national mourning for someone Ghana's President Nana Akufo-Addo called "one of the truly iconic figures of modern times".

'Stubborn optimist'
Many ordinary Ghanaians described him as a father-figure and a source of national pride, while his brother, Kobina, told the congregation that he was not just a leader and statesman.

"We lost a brother, a husband, a father, a grandfather and an uncle, a man of deep conviction who was as committed to instilling the values of fairness, integrity, kindness and service in each of us as he was to advocating for peace and human rights around the world," he said.

"Stubborn optimist that he was, he would want us all to look forward with hope and keep striving to create a freer, fairer and more peaceful world."

The current UN Secretary General, Antonio Guterres, praised his close friend as an "exceptional global leader" who was dignified, courageous and a man of "integrity, dynamism and dedication".

"Kofi Annan was the United Nations and the United Nations was him," he added. (AFP)

•Nane Maria, the widow of Kofi Annan, Ghanaian diplomat and former Secretary General of United Nations who died on August 18 at the age of 80 after a short illness, stands in front of his coffin at the Accra International Conference Centre in Accra on September 12, 2018.

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