|Jeremy Ractliffe and Naomi Campbell|
(Story reported by Aislinn Laing for the UK Telegraph)
Jeremy Ractliffe, 74, said in his resignation letter that he recognised his failure to tell the charity about the diamonds - which Miss Campbell said she gave to him as a donation to the fund - was wrong.
He admitted he had also left himself open to prosecution - the possession of uncut diamonds is illegal in South Africa - and if he had told the charity’s board, and its founder Nelson Mandela, they could have dealt with the gems in a “better and lawful” way.
"Mr Ractliffe has apologised to the Chairperson, Chief Executive Officer, the board and the Nelson Mandela Children's Fund (NMCF) for the anxiety and possible reputational risk his conduct may have caused," a statement released by the fund read.
"For these reasons, he considers it correct and proper for him not to make himself available for re-election as a trustee at the forthcoming annual general meeting of NMCF on 27 August. Mr Ractliffe has also undertaken to resign as a board member of the USA affiliate of the NMCF with immediate effect."
During the war crimes tribunal of former Liberian president Charles Taylor, Miss Campbell said she was given three “dirty-looking pebbles” by two men who knocked on her door in the small hours following a dinner hosted by Mr Mandela and attended by Taylor in Pretoria in 1997.
(click here to read the full story on Jeremy Ractliffe and here to watch Naomi Campbell's testimony implicating Ractliffe on the UK Telegraph website)