Britain\'s Prince Charles took a break from sight-seeing in South Africa on Saturday to deliver a call to save the planet\'s natural resources. Speaking on the last full day of his four-day South Africa tour with wife Camilla, Charles said an \"unholy combination\" of climate change, increasing food demand and intensifying urban development is jeopardising the planet\'s health. \"There is mounting evidence that, worldwide, we cannot carry on as we have been without suffering some very painful consequences,\" he said in a speech at the University of Cape Town. \"There is a growing mismatch between what we demand of the Earth\'s resources and the ability of nature\'s systems to respond.\" The prince\'s call to action comes three weeks before the next round of UN climate talks kicks off in Durban, South Africa. He quipped that his hosts must be either \"kind or rash\" to invite him to talk climate change on the eve of the meeting. Earlier, Charles visited a sustainable fisheries project while Camilla attended a literacy event in a poor township neighbourhood. Their visit has also taken them to landmarks of the anti-apartheid struggle in Johannesburg and a game reserve in KwaZulu-Natal province. They will attend a church service Sunday in Cape Town before leaving for Tanzania.