LONDON , England ( CNN ) -- Hollywood star Will Smith led a London crowd of 46,664 in a chorus of `` Happy Birthday '' to Nelson Mandela on Friday at a party for the South African prisoner , president and Nobel Peace Prize winner . Nelson Mandela had a smile and a message . Smith introduced Mandela to the London crowd celebrating Mandela 's life with the words `` The one , the only , the birthday boy , Nelson Mandela , Nelson Mandelaaaaaaaaaa . '' London was the scene of a concert 20 years ago to celebrate Mandela 's 70th and to raise awareness of his imprisonment . Mandela told cheering fans , `` Your voices carried across the water to inspire us in our prison cells far away . Tonight , we can stand before you free . `` We are honored to be back in London for this wonderful occasion . `` But even as we celebrate , let us remind ourselves that our work is far from complete . `` Where there is poverty and sickness , including AIDS , where human beings are being oppressed , there is more work to be done . Our work is for freedom for all . '' Watch Mandela at the party » . As Mandela walked on stage , Smith led the crowd in a chorus of `` Happy Birthday . '' Proceeds from the concert in London 's Hyde Park will go toward the 46664 Campaign , which Mandela founded in 2003 to raise awareness about the impact of AIDS , especially in Africa , and to promote HIV-prevention measures around the world . The name of the charity represents Mandela 's prison number when he was incarcerated at Robben Island . Organizers put 46,664 tickets up for sale . The finale of the concert saw Queen , Amy Winehouse and Jerry Dammers performing `` Free Nelson Mandela , '' a 1980s hit from the Specials that quickly became an anti-apartheid anthem , with pretty much every act joining them on stage . Watch stars perform for Mandela » . Dammers was also one of the driving forces behind the London concert in 1988 to awareness of Mandela 's long imprisonment by the South African authorities . The former South African president turns 90 on July 18 . Watch the crowd celebrate » . Speculation surrounded whether Winehouse would perform after being hospitalized with lung problems last week . More than a dozen African artists , including Johnny Clegg and the Soweto Gospel Choir , performed . Smith , music legend Quincy Jones and Formula One driver Lewis Hamilton were among the stars introducing acts . Other guests at the concert included British Prime Minister Gordon Brown , former U.S. President Clinton , talk show host Oprah Winfrey and actor Robert De Niro . Mandela served as his country 's first democratically elected president from 1994 to 1999 . In recent years , he has campaigned on behalf of HIV and AIDS awareness and has long called the battle against AIDS a basic human right . In 1964 , a court sentenced Mandela to life in prison for plotting to overthrow the government by violence . He spent the first 18 years at Robben Island Prison , off Cape Town , South Africa , and later spent time at Pollsmoor prison and Victor Verster Prison , closer to the mainland . While in prison , Mandela became recognized as the most significant black leader in South Africa , and he became a potent symbol of resistance in the anti-apartheid movement . Mandela consistently refused to compromise his political position to obtain his freedom . South African President F.W . de Klerk released Mandela in February 1990 after 27 years in prison . Mandela was elected president of the African National Congress the following year , and in 1994 , he was elected president of his country .
Celebrities , who gather in London to celebrate King 's 90th birthday . Mandela at outdoor concerts in his honour in London 's Hyde Park . Crowd of 46,664 . ` ` Happy Birthday '' written by Will Smith . Artists include Amy Winehouse , Queen , Annie Lennox , Simple Minds .