Obama also met with former French President Francois Hollande, who said in a tweet that climate change was among the issues they discussed nearly two years after they both signed the Paris agreement.
Earlier this year, Trump declared that the US would no longer be a part of the landmark 2015 accord with 196 countries, claiming the non-binding agreement imposed unfair standards on American businesses and workers. "And that's a hard position to defend", Obama said, according to The Chicago Tribune.
Obama spoke for about 15 minutes at the North American Climate Summit in Chicago, which was hosted by his former chief of staff and Chicago Mayor Rahm Emanuel (D). "I am proud to stand together with the leading global city climate networks including the Global Covenant of Mayors, Climate Mayors and C40 to take decisive action to improve our environment while bettering our communities, and that begins right here". His decision marked a major setback to worldwide efforts to combat climate change and placed the U.S.in opposition to the stance of some of the country's closest foreign allies. Trump has said the terms of the agreement should be more favourable to businesses and taxpayers. The Paris accords set targets for reducing greenhouse gas emissions and limiting the rise in average global temperatures. It also calls for them to work with scientific and academic experts to find solutions.
He says 51 mayors will sign a charter and discuss solutions including expanding access to public transportation.
Emanuel said Trump and his environmental officials are in denial on climate change.
"But the good news is that the Paris agreement was never going to solve the climate crisis on its own".
In lieu of the nation's withdrawal from an worldwide agreement on climate change, 50 municipal leaders from around the country, including Portland Mayor Ted Wheeler, signed a charter Tuesday committing their cities to emissions reductions.
Other mayors attending include Valerie Plante of Montreal and Miguel Angel Mancera of Mexico City.