Agence France-Presse: UN chief Ban Ki-moon on Wednesday demanded a breakthrough from the Bali talks on framing an answer to climate change, but weary negotiators admitted this goal seemed elusive. Environment ministers or their stand-ins from more than 180 countries have until Friday to agree a framework for tackling global warming past 2012, when pledges under the Kyoto Protocol expire. "If we leave Bali without such a breakthrough, we will not only have failed our leaders but also those who …