President Donald Trump announced on Thursday that he would be withdrawing the United States from the Paris Climate Agreement that was established in 2015 at COP21.

Who's Supporting the Paris Climate Agreement? 

Elected officials around the country and business moguls took to Twitter after Trump’s announcement to react to the decision, many saying it was a step backwards for the country. The agreement was signed under President Barack Obama, who favors green alternatives and believes in climate change, on Thursday he released a statement in which he called Trump’s decision a “lack of American leadership.” Elon Musk, Leonardo DiCaprio and Neil deGrasse Tyson, climate change advocates, also weighed in on the decision.

Read: What Is The Paris Climate Agreement?

Obama Climate U.S. President Barack Obama delivers a statement on the climate agreement at the White House in Washington, Dec. 12, 2015. Photo: Reuters/Yuri Gripas

In the wake of the announcement many elected officials announced that even if the Trump Administration would not support the agreement, they would be supporting it on a state and local level.

The governors of California, Washington and New York almost immediately formed the United States Climate Alliance, according to press releases. The alliance will be a “coalition that will convene U.S. states committed to upholding the Paris Climate Agreement and taking aggressive action on climate change,” said a release from New York Governor Andrew Cuomo’s office. The three states working to establish the alliance have a total population of about 68 million people accountable for ten percent of the country’s emissions. The governors hope that more governors across the country will join them.

Read: Larsen C Ice Shelf Break Rapidly Heading Toward Creating Massive Iceberg

In addition to the governors’ pledge to reduce emissions, a coalition of 84 mayors also pledged to “adopt, honor, and uphold the commitments to the goals enshrined in the Paris Agreement,” according to a post from the Climate Mayors, also called the Mayors National Climate Action Agenda. The group was established after the Paris Agreement was signed to create a way for mayors to communicate on a city to city level. The group was founded by the mayors of Los Angeles, Philadelphia and Houston.

Mayor Marty Walsh of Boston pledged to uphold the agreement a sentiment he echoed on Twitter Thursday evening with a photo of City Hall lit up green for the environment.

Other cities also lit their monuments green, in Trump’s hometown of New York City multiple monuments were lit green for the evening.

Mayors and governors were committing to signing executive orders to uphold initiatives to lower greenhouse gas emissions including Pittsburgh Mayor Bill Peduto and New York City Mayor Bill de Blasio.

The full list of mayors who are planning to uphold the Paris Climate Agreement can be viewed here.

So far the governors who have committed to upholding the agreement include:

California Governor Jerry Brown, New York Governor Andrew Cuomo, Washington Governor Jay Inslee, Massachusetts Governor Charlie Baker, Oregon Governor Kate Brown, Colorado Governor John Hickenlooper, Hawaii Governor David Ige, Connecticut Governor Dan Malloy, Virginia Governor Terry McAuliffe and Rhode Island Governor Gina Raimondo.

paris President Donald Trump announces his decision that the United States will withdraw from the Paris Climate Agreement, in the Rose Garden of the White House in Washington, D.C., on June 1, 2017. Photo: REUTERS

What Is The Paris Climate Agreement?

The agreement sets climate goals and helps countries plan to cut emissions over the coming years to keep climate change to 2 degrees Celsius, or about 3.6 degrees Fahrenheit.

President Trump said the agreement “disadvantages the United States.” He also repeatedly called the agreement, that emphasizes a switch to renewable energy resources and lower greenhouse gas emissions, a “bad deal.”

There are only three countries that are now not in the Paris Climate Agreement: U.S., Syria and Nicaragua.