Nelson Mandela has celebrated the 20th anniversary of his release from prison with a special dinner, inviting ex-wife Winnie and one of his former jailers.

Mr Mandela, who became South Africa's first black president, was freed from Robben Island jail on 11 February 1990 after a prison sentence of 27 years.

Mr Mandela has said he developed a friendship with warder Christo Brand that cemented his views of humanity.

Mr Mandela's daughter, Zindzi, and a number of anti-apartheid activists who were there when he walked free, also attended the small gathering on Thursday night.

Zindzi Mandela filmed the dinner for a documentary called Conversations About That Day, which will be shown on the anniversary next week.