South Africa's Desmond Tutu has accused his country of betraying its anti-apartheid legacy by failing to take strong action against Zimbabwe's President Robert Mugabe.
Archbishop Emeritus Tutu, a Nobel peace prize winner, also says military force against Mr Mugabe's government should not be ruled out.
"How much more suffering is going to make us say, 'No, we have given Mr Mugabe enough time?'," he asked in an interview with the BBC.
While neighbouring countries Botswana and Zambia have taken a tough line against the Mugabe regime, South Africa has stopped short of calling on him to quit. It has strong historic links with Mr Mugabe, who provided support during the country's struggle against apartheid.
The former archbishop also criticised South Africa for not taking tougher stands at the United Nations against countries with a record of human rights abuses.
"I am deeply, deeply distressed that we should be found not on the side of the ones who are suffering," he said.
"I certainly am ashamed of what they've done in the United Nations."