World largest cities' mayors unite against climate change
Mayors of 63 of the world's largest cities pledged to redouble efforts to combat climate change, while claiming energy-from-waste, bike-sharing and other schemes have already made an impact. Duration: 00:46
Mayors of 63 of the world's largest cities pledged to redouble efforts to combat climate change, while claiming energy-from-waste, bike-sharing and other schemes have already made an impact. Duration: 00:46