Apple, Amazon, Google, Lyft and Spotify are among hundreds of U.S. businesses teaming up with state and local regulators to pledge their support for the Paris climate agreement as part of a new campaign debuting today.

The broad effort, called “We Are Still In,” comes days after President Donald Trump announced his plans to withdraw from the pact, a landmark accord signed in 2015 by roughly 190 nations that seeks to reduce the world’s carbon emissions.

The vast coalition will be led by Michael Bloomberg, the former mayor of New York City, the sources said. A spokesperson did not immediately comment for the story, but a website for it appears to suggest that more information is coming later today.

For now, though, their opening salvo is a public commitment: Tech giants, along with other business and political leaders, said they are “joining forces for the first time to declare that we will continue to support climate action to meet the Paris Agreement.”

“The Trump administration’s announcement undermines a key pillar in the fight against climate change and damages the world’s ability to avoid the most dangerous and costly effects of climate change,” according to a copy of the missive shared by sources with Recode. “Importantly, it is also out of step with what is happening in the United States.”

“In the U.S., it is local and state governments, along with businesses, that are primarily responsible for the dramatic decrease in greenhouse gas emissions in recent years,” the note continues. “Actions by each group will multiply and accelerate in the years ahead, no matter what policies Washington may adopt.”

Announcing his intent to leave the Paris agreement during a speech in the White House’s Rose Garden last week, Trump said it “disadvantages the United States, to the exclusive benefit of other countries,” while arguing that it left “American workers, who I love, and taxpayers to absorb the costs.”

Hours after Trump revealed his thinking, however, many state leaders, city mayors and U.S. businesses declared their opposition — while tech giants in Silicon Valley, which often have fought Trump, once again declared war on the White House.

Facebook CEO Mark Zuckerberg described the decision to withdraw as “bad for the environment, bad for the economy, and it puts our children's future at risk.” Top executives at Google and Twitter tweeted similarly, and SpaceX founder Elon Musk, who has advised Trump on business issues, even said he would cease participating on the president’s economic councils. In a note to employees, obtained last week by Recode, Apple CEO Tim Cook also expressed his “disappointment” with Trump’s move. The iPhone giant’s chief even called the president — days before Trump announced his plans — to try to persuade him to keep the U.S. in the agreement.

Some of those companies previously joined with other business leaders to run full-page advertisements in major newspapers that pleaded with Trump to remain part of the Paris pact. The deal would have expanded “markets for innovative clean technologies,” they said, which could spur economic growth and job creation. And companies expressed fear that withdrawing would “expose us to retaliatory measures” from other countries’ governments.

Read the new, full letter, as obtained by Recode:

We, the undersigned mayors, governors, college and university leaders, investors and businesses, are joining forces for the first time to declare that we will continue to support climate action to meet the Paris Agreement. In December 2015 in Paris, world leaders signed the first global commitment to fight climate change. The landmark agreement succeeded where past attempts failed because it allowed each country to set its own emission reduction targets and adopt its own strategies for reaching them. In addition, nations – inspired by the actions of local and regional governments, along with businesses – came to recognize that fighting climate change brings significant economic and public health benefits. The Trump administration’s announcement undermines a key pillar in the fight against climate change and damages the world’s ability to avoid the most dangerous and costly effects of climate change. Importantly, it is also out of step with what is happening in the United States. In the U.S., it is local and state governments, along with businesses, that are primarily responsible for the dramatic decrease in greenhouse gas emissions in recent years. Actions by each group will multiply and accelerate in the years ahead, no matter what policies Washington may adopt. In the absence of leadership from Washington, states, cities, colleges and universities and businesses representing a sizeable percentage of the U.S. economy will pursue ambitious climate goals, working together to take forceful action and to ensure that the U.S. remains a global leader in reducing emissions. It is imperative that the world know that in the U.S., the actors that will provide the leadership necessary to meet our Paris commitment are found in city halls, state capitals, colleges and universities, investors and businesses. Together, we will remain actively engaged with the international community as part of the global effort to hold warming to well below 2°C and to accelerate the transition to a clean energy economy that will benefit our security, prosperity, and health.

Sign up for the newsletter Recode Daily Email (required) By signing up, you agree to our Privacy Notice and European users agree to the data transfer policy. Subscribe