For now, the alliance includes California, New York and Washington State.
The Paris agreement marked a turning point in the global fight against climate change, uniting nearly 200 nations worldwide to legally ratify action against pollution. With the White House unwilling to take climate change seriously, they will have to continue to lead the way.
California already has several climate change agreements in place with Chinese regional and national governments, but Brown says the state can do more.
"While the USA decision is disheartening, we remain inspired by the growing momentum around the world to combat climate change and transition to clean growth economies".
President Donald Trump today withdrew the USA from the landmark Paris climate accord which he said was not tough on India and China, and alleged that the deal was negotiated "poorly" by the Obama administration and signed out of "desperation".
"If we do nothing, our children will know a world of migrations, of wars, of shortage", Macron noted.More news: Mbappe to consult Deschamps over future amid Real Madrid links
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He said the deal "hamstrings" America by giving foreign nations an "economic edge", adding, "that's not going to happen".
Jerry Brown and Washington Gov. Jay Inslee said it falls on states to curb emissions following the Trump administration's decision.
Under former President Barack Obama, the USA had agreed to reduce emissions to 26 percent to 28 percent of 2005 levels by 2025 - about 1.6 billion tons. "Pittsburgh stands with the world & will follow Paris Agreement".
Tokyo will take advantage of upcoming worldwide meetings such as a G-7 environment ministers' meeting later this month and a Group of 20 summit next month to tell the United States that its economy will benefit if it opts to fight climate change within the framework of the Paris Agreement, government officials said.
"We could have lived with a modified Paris Climate Agreement", said Lignite Energy Council President Jason Bohrer, who indicated the country's removal from the agreement reduces the risk that a future president may use the agreement as an excuse to clamp down on carbon dioxide emissions again.
In wake of Trump's announcement, Tim Cook has sent an email to Apple staff reiterating the company's stance on climate change and slamming the president's decision...
The governors echoed Trump's predecessor President Barack Obama, whose administration committed to the deal.