London, England (CNN) -- "If we don't get it right we are all done for," Archbishop Desmond Tutu says of efforts to combat climate change.
"This is not crying wolf. This is the only world we have. If this world disappears, whether you are rich are poor, whether you are free or oppressed the fate is the same for all of us."
The 78-year-old cleric was speaking to CNN's Becky Anderson from the U.N. climate summit in Copenhagen.
He urged western leaders to firm up their commitments and agree on greenhouse gas reductions. "All we want is for them to commit to reducing emissions levels by 80 percent of the levels that they had in 1990."
Tutu has spent his life spreading messages of peace and unity. Now he is hoping to help convince leaders at the U.N. climate summit of the urgency of their quest.
He called on richer countries to assist developing countries. "We need money. Billions," he said. "But then you've got the money -- you bailed out the banking system."
A former Nobel peace prize winner, Tutu was the first black leader of the Anglican Church in South Africa and was an outspoken critic of apartheid. Since the end of apartheid in 1994 Tutu has campaigned for peace in troubled regions worldwide.
Asked by Anderson whether western countries should boycott Israel as they did with apartheid Tutu said: "Israel has every right to its security, every right to its sovereignty, every right to defends itself. But the best way Israel has of living in peace is when they show justice towards the Palestinians. Otherwise, as sure as anything, what they are doing is creating a group of people with deep, deep resentments."
He added: "I have been very greatly influenced by Hebrew prophets in my own opposition to the injustice of apartheid or injustice anywhere in the world. You want to use all non-violent ways of ensuring that it changes."
Tutu says he still reads the Bible everyday but recommends that people don't believe everything it teaches.
"You have to understand is that the bible is really a library of books and it has different categories of material," he said.
"There are certain parts which you have to say no to. The Bible accepted slavery. St Paul said women should not speak in church at all and there are people who have used that to say women should not be ordained. There are many things that you shouldn't accept."