Agence France-Presse: Former US President Bill Clinton urged leaders of the world’s cities, which produce over two-thirds of greenhouse gas emissions, to act swiftly to save the planet for their grandchildren. Executives from the 40 largest cities plus 17 affiliate municipalities attended the C40 Large Cities Climate Summit which opened in Seoul, the third such event since 2005. The former US leader, whose Clinton Climate Initiative develops programmes to help cities cut the emissions blamed for …