Cop26 is “the last chance saloon” to save the world from runaway climate change, Prince Charles has told world leaders in Rome ahead of the crucial climate summit in Glasgow.Speaking to an audience including Boris Johnson on the sidelines of the gathering of the G20 group of industrialised nations, Charles said it was the moment to begin a green-led economic turnaround.“Ladies and gentlemen, Cop26 begins in Glasgow tomorrow,” Charles said. “Quite literally, it is the last chance saloon. We must now translate fine words into still finer actions.“And as the enormity of the climate challenge dominates people’s conversations, from newsrooms to living rooms, and as the future of humanity and nature herself are at stake, it is surely time to set aside our differences and grasp this unique opportunity to launch a substantial green recovery by putting the global economy on a confident, sustainable trajectory and, thus, save our planet.“And, from what they tell me, the private sector is already there, eager to work with you and ready to play a hugely significant and gamechanging role. This is why I am so grateful to have this chance to talk to you here today, and to shine a light not just on how far we’ve come, but also on how far we still need to go.”Charles’s intervention came as Johnson prepared to greet more than 120 world leaders at the start of the two-week Cop gathering on Monday, with the UK prime minister using much of his time at the G20 event to push home a similar message that concerted global action is required.2050: what happens if we ignore the climate crisis – video explainer On his way to Rome on Friday, Johnson told reporters that the success of Cop remained in the balance, likening the world’s struggle against the climate emergency to a football team losing 5-1 at half-time.In comments on Saturday, Johnson said a lack of progress in Glasgow could prompt “very difficult geopolitical events” including mass migration and global competition for food and water.In his speech, Charles stressed what he called “our overwhelming responsibility to generations yet unborn”, saying he detected a change in attitudes and “the buildup of positive momentum”.Highlighting the need for the private sector to also tackle the issue, Charles said it would need trillions of dollars of investment every year to limit warming to the target maximum of 1.5C above pre-industrial levels.“No government has those sorts of sums, which is why I have spent so much time over the past 19 months trying to form a global alliance amongst the private sector, as I have long believed it holds the ultimate key to the solutions we seek,” he said.Governments in turn needed to provide long-term leadership on the issue, as well as regulatory and financial support, he added.