BBC: Ministers cancelled morning press engagements, reportedly to engage in further last-minute diplomacy. Late on Thursday there was optimism about an agreement, despite fears it might not prevent a "catastrophic" 3C (5.4F) temperature rise. Denmark’s prime minister had spoken of "very fruitful" talks just before US President Barack Obama arrived in Copenhagen for talks with 118 other world leaders. Both the US and China, the two largest emitters of greenhouse gases, …