Ahead of a meeting of the G20 group of leading nations in China, 30 mayors from cities worldwide have called for rapid ratification of the Paris climate deal.
Sadiq Khan, the Mayor of London, joined Mayors from other cities including Paris, Tokyo, Sydney, New York, Cape Town and Rio de Janeiro to call on national leaders to work together to 'build a low carbon, climate safe world'.
The open letter from the mayors stated: ''To limit the global temperature increase to 1.5C above pre-industrial levels, global greenhouse gas emissions need to peak by 2020. Achieving such a rapid shift is probably one of the greatest political, economic and practical challenges faced by every national leader, but you do have great allies in this task: we, the mayors of the megacities of the world.''
Many cities are already dealing with the consequences of climate change, from tackling floods to heatwaves.
Leaders have committed to creating plans for how they will deliver the greenhouse gas cuts in their cities which are needed to help meet the goals of the Paris Agreement and avoid dangerous climate change. They said: ''We want our citizens, markets and other political leaders to know that we are serious about making the Paris Agreement a reality. We call on the heads of states from our respective nation states to do the same.''
