The Nelson Mandela Children's Fund (NMCF) trustee who two weeks ago revealed that he received uncut diamonds from British model Naomi Campbell has resigned with immediate effect, the fund said on Wednesday.

Jeremy Ratcliffe kept the diamonds for 13 years, disclosing their whereabouts only after Campbell testified at The Hague in the war crimes trial of former Liberian leader Charles Taylor on Aug. 5 this year.

On Wednesday NMCF board said in a statement to the South African Press Association (SAPA) "Mr Ratcliffe regrets his omission to inform the chairperson, and the rest of the board of trustees of the NMCF of his receipt of the uncut diamonds until now and acknowledges that had he done so, he and the board would have found a better and lawful way to manage the situation,"

Ratcliffe received the three uncut diamonds from Campbell in 1997.

According to SAPA, he told the board he would not avail himself for re-election at its annual general meeting later in August.

Ratcliffe apologized to the board for the "possible reputational risk" his conduct may have caused. He also realized that he had left himself open to possible prosecution.

In its statement the board accepted Ratcliffe's apology and his decision to step aside.

In South Africa, a person found in possession of uncut diamonds, without a license, faces 10 years imprisonment or a 250,000 rand (34,000 U.S. dollar) fine or both.

Ratcliffe earlier admitted that he took and kept three small uncut diamonds given to Campbell so she would not get into trouble.

On Aug. 5 he handed the stones to South African police.

Campbell testified in The Hague that she was given the stones while on a visit to South Africa. She assumed they were from former Liberian president Charles Taylor. Ratcliffe told the fund that he acted in a way he "sincerely believed" was in its best interests. South African police are investigating the circumstances surrounding the uncut diamonds.