Urban 20 (U20) is an initiative developed in 2017 under the leadership of the Mayor of Buenos Aires and Mayor of Paris, and convened by the C40 Cities Climate Leadership Group (C40) in collaboration with United Cities and Local Governments (UCLG). U20 seeks to develop a joint position and collective messages to inform and enrich the discussions of national leaders at the G20 Summit through unique urban perspectives. Tokyo has been participating in the U20 from 24 January 2018.
In 2019, as Japan will host the G20 Summit, Tokyo will host the second U20 Mayors Summit. Mayors of participating cities are invited to the U20 Mayors Summit to discuss and approve a communiqué, which will be formally presented to the G20.