The former South African president who engineered the end of apartheid has said in London that boycotts of Israel would be ineffective.
Before addressing the Anne Frank Trust Holocaust Memorial Day lunch at the Hilton Park Lane, F W de Klerk recalled that "boycotts in South Africa kept us on our toes but on balance, they delayed change, delayed reform. What happens when a country is boycotted is that people suffer as a result. People say: 'Those who boycott us are our enemies.'
"In our case, it delayed the peace. The agent of change is economic development. If you stifle the economy, people feel marginalised. You can apply this to those who try to use boycotts against Israel."
Those working towards Middle East peace could learn lessons from the South African experience. "I think one of the keys to our success in negotiation was that from both sides - ours and Nelson Mandela - there was a willingness to really try and understand and accommodate the concerns of the other side.
"You must put yourself in the position of your opponent and understand what it is reasonable."
Mr de Klerk received a standing ovation from the 630 lunch guests for a speech in which he praised Mr Mandela. He called for the rejection of "all ideologies, whether secular or religious, that place this or that utopian or religious vision above the right to life, happiness and dignity of ordinary human beings".
The lunch raised £275,000 for the work of the Anne Frank Trust.