Nobel Laureate, Archbishop Desmond Tutu, dances with the cast of the Isango Ensemble, after their performance of The Magic Flute, which formed part of a surprise birthday celebration, on October 1, 2011 in Cape Town. In front of Tutu is one of two birthday cakes presented for the occasion. The celebration for Tutu's birthday which is on October was organised by his daughte, Mpho, a group of charities of which Tutu is patron, and the Isango opera company.

Desmond Tutu at the first of many parties for his 80th birthday. Photo: AFP

A NEW biography to mark Desmond Tutu's 80th birthday on Friday celebrates the South African icon as a tireless activist and playful inspiration in tributes from world leaders to rock stars.

The book contains intimate accounts from a diverse collection of friends made during his globe-trotting campaigns to end apartheid in South Africa and then for peace and justice in the rest of Africa and worldwide.

''I believe that God is waiting for the archbishop. He is waiting to welcome Desmond Tutu with open arms,'' South Africa's first democratic president and fellow Nobel peace laureate Nelson Mandela said. ''If Desmond gets to heaven and is denied entry, then none of the rest of us will get in!''

The book traces the transformation of a clergyman to a global icon.

''Emotionally and mentally, Bishop Tutu and I are very close. I call him my spiritual older brother,'' Tibet's Dalai Lama said.

Copies of letters to apartheid rulers and handwritten extracts of his notes reveal his relentless fight for democracy.

A 1985 letter to F. W. de Klerk, South Africa's last apartheid president, demands a passport to replace a document listing Archbishop Tutu's nationality as ''undeterminable at present''.

The archbishop then goes on to blast the ''policy of apartheid as utterly evil, un-Christian and immoral'', before signing off with ''God bless you''.

''I developed tremendous respect for his fearlessness. It wasn't fearlessness of a wild kind. It was fearlessness anchored in his deep faith in God,'' Mr de Klerk said in the book.

Archbishop Tutu's trademark playfulness is dotted throughout the book, by his youngest daughter Mpho and veteran journalist Allister Sparks.

Mogul Richard Branson recalls teaching him how to swim and Burma's Aung San Suu Kyi calls him a ''sort of giggle-maker''. The book also recalls the archbishop asking for directions in 1960s Britain, just to be called ''sir'' by a white policeman.

Irish rocker Bono describes how Archbishop Tutu led his unsuspecting band on their first meeting from his Cape Town office to a packed hall before smiling and telling the crowd: ''Here are U2 to sing for you.''

Intimate peeks into the archbishop's life are offered in moments spent with wife Leah, with the couple kneeling to be blessed on their 25th wedding anniversary.

''It's a challenge,'' his wife said of living with a public figure. She admits to throwing clods of earth and fruit at tourists gawking over her fence in Soweto.

Bob Geldof calls him a showman and the ''smallest giant I've ever met''.

''For those in power, Arch is a complete pain in the arse,'' he says. ''He calls it as he sees it and he never shuts up.''

One of the most personal accounts is from Mr Mandela's current wife, Graca Machel, who speaks of sometimes becoming ''overwhelmed'' by her responsibilities.

''Sometimes I feel like I'm too small to know how to do the right thing. At these times, I will approach the Arch and he will give me the guidance I need to make me feel that everything is fine.'' AFP