The mayor of London , Los Angeles , Paris , Copenhagen , Barcelona , Quito , Vancouver , Mexico City , Milan , Seattle , Auckland , and Cape Town have just charge to a sheer plan to clean up their metropolis ' aura and tranquillise the wider scourge of mood modification .

On Monday , the 12 mayor sign on the " C40 Fossil - Fuel - Free Streets Declaration " , uniting in a promise to only use zero - expelling buses by 2025 and make the “ major areas ” of their cities liberal of fossil fuel emissions by 2030 . They also agree to reduce the number of foul vehicle on the streets and boost clean agency of getting around , such as walking , cycling ,   public   transfer , and carpooling .

The push was made at a summit for theC40 Cities initiative , an international connection of over 90 cities working to address the peril of clime variety . Together , they arecollaborating on plansto turn the targets set by the Paris Agreement into reality . This admit many US cities , in spite of President Donald Trumppulling out of the agreementin July 2017 .

“ The tumid sources of tune pollution are also the largest germ of C emissions   – and in many metropolis , transportation is the biggest culprit , ” Michael Bloomberg , UN Special Envoy for Cities and Climate Change , former Mayor of New York , and C40 Board President , read ina command .

“ C40 Mayors realize boom cities require clean air . By shift to cleaner vehicle , we can fight mood change and save many lives . ”

These 12 cities are base to over 80 million citizenry . Urban areas only describe for around 2 percent of the world ’s landmass yet they pump out over 70 percent of global carbon emission and consume two - third of the world ’s zip . Furthermore , 70 percent of the city in the C40 initiative report they are already feel the strain of climate change .

On Sunday , the summit also saw30 major city city manager and older executives from some of the world ’s most powerful companies , include Volvo , Mercedes - Benz , and Siemens , discuss the threats and solutions to climate change .

“ As cities take clime action , they can do good for their residents and do well for their urban thriftiness , " said Hany Fam , EVP Enterprise Partnerships of Mastercard , one of the multinational companies who wait on the discourse .

" By come together as a private sector , we can make go around metropolis more unseamed and more sustainable . ”