Former Robben Island prisoner Tokyo Sexwale cuts a cake made in honour of Nelson Mandela during his 90th birthday celebration at the prison on Friday. The number on the cake 46664 is Mandela's prisoner number. (Schalk van Zuydam/Associated Press)

Anti-apartheid icon Nelson Mandela called on the wealthy to share with those less fortunate as he celebrated his 90th birthday on Friday.

Mandela said he feels lucky to have reached the age of 90, but many of the poor are unlikely to live that long.

"There are many people in South Africa who are rich and who can share those riches with those not so fortunate who have not been able to conquer poverty," Mandela said in an interview Friday at his home in rural South Africa.

Mandela made the comment during a brief interview with a gathering of reporters in the private lounge of his Qunu home.

"This is my property. When I am here, I feel I own something," he said, referring to the rural area 950 kilometres south of Johannesburg where he spent his youth.

Soon after the interview, a group of seven or eight grandchildren crowded around Mandela's chair, sang Happy Birthday to You and kissed him.

The room was full of birthday presents from all over the world and included a portrait, a bust, a collection of photography books — all featuring him — from well-known artists.

Birthday annual cause for celebration

Mandela spent 27 years in prison for his fight against apartheid. After he was released in 1990, he led negotiations to end white rule in the country and was elected president in South Africa's first fully democratic elections in 1994.

He chose not to run again after completing his term in 1999, but continued to fight poverty, illiteracy and AIDS in Africa.

At first, Mandela planned quiet celebrations in his hometown, but a variety of events were planned in his honour for Friday and Saturday.

The events included a soccer festival, a pop concert and lunch for 500 politicians and veterans of the anti-apartheid struggle and other guests at his home Saturday.

His birthday is annual cause for celebration in South Africa and draws attention from his many local and international admirers.

South Africa has been celebrating since the start of the year, with museum exhibitions, reunions of anti-apartheid veterans, a weekend speech by Liberian President Ellen Johnson Sirleaf, and the launch of special coins and stamps.

Children write birthday wishes to Mandela

In Mandela's hometown, the small southeastern village of Qunu, residents spent Thursday readying for the birthday celebrations by mowing the lawn outside a tiny museum dedicated in his honour, laying new tarmac on the road outside his house and practicing a song created especially for him.

"We are very excited," Nkalane Junior Secondary School principal Mpondomise Ndzambo said Thursday, sitting in his office beneath a photograph of the former president. "Usually these celebrations are done in Johannesburg, so this is a way of being part of it."

The school enjoys a special relationship with the local hero. Mandela helped raise funds so it could build new classrooms and move out of a dilapidated mud structure.

"He has done a lot for us, specially for the school," Ndzambo said. "He suffered a lot trying to get this South Africa to be free and fair. I think he is a great man."

Yaneliswa Khandawuli, 16, wrote a poem for the occasion, dedicated to the "hero of the heroes."

"Nelson Mandela changed our lives," she said. "All of us, black and white, we are now the rainbow nation. I love him very much."

Khandawuli wished Mandela a long life and a happy day. But she really wished for something for herself.

"I don't want God to take him away from us," she said.

With files from the Associated Press