 -- The reaction to President Donald Trump's decision to withdraw the U.S. from the Paris Climate Agreement was swift Thursday evening.

In a press conference at the White House today, President Donald Trump announced that, although the U.S. will no longer participate in the accord, it will begin negotiations to possibly re-enter the Paris Agreement or work on a new accord with terms that he believes are more fair to the United States.

"So we are getting out but we are starting to negotiate and we’ll see if we can make a deal that’s fair," Trump said.

Reactions from politicians, business leaders and environmental organizations came quickly across social media.

Politicians

President Barack Obama

Obama issued a statement saying he believes the U.S. should be at the "front of the pack," leading the remaining nations that will "reap the benefits."

"A year and a half ago, the world came together in Paris around the first-ever global agreement to set the world on a low-carbon course and protect the world we leave to our children," Obama said.

He expressed confidence in Americans to continue to lead the way to protect the environment.

"But even in the absence of American leadership; even as this Administration joins a small handful of nations that reject the future; I’m confident that our states, cities, and businesses will step up and do even more to lead the way and help protect for future generations the one planet we’ve got," Obama said.

House Speaker Paul Ryan

"The Paris climate agreement was simply a raw deal for America," said Ryan. "Signed by President Obama without Senate ratification, it would have driven up the cost of energy, hitting middle-class and low-income Americans the hardest. In order to unleash the power of the American economy, our government must encourage production of American energy. I commend President Trump for fulfilling his commitment to the American people and withdrawing from this bad deal."

Hillary Clinton

Former Secretary of State John Kerry

Kerry wrote a Facebook post and called the move to withdraw from the Paris agreement a "big mistake" that "isolates the United States after we had united the world."

"The President who promised 'America First' has taken a self-destructive step that puts our nation last," Kerry said. "This is an unprecedented forfeiture of American leadership which will cost us influence, cost us jobs, and invite other countries to walk away from solving humanity’s most existential crisis."

Senate Majority Leader Mitch McConnell

"I applaud President Trump and his administration for dealing yet another significant blow to the Obama Administration’s assault on domestic energy production and jobs," said McConnell. "President Obama made commitments in this deal based off a costly power plan that we knew at the time was on shaky legal ground. By withdrawing from this unattainable mandate, President Trump has reiterated his commitment to protecting middle class families across the country and workers throughout coal country from higher energy prices and potential job loss. Today’s move builds on action Congress took to rebuff then-President Obama’s regulatory rampage, which put American jobs at risk. When the previous administration signed America up for this unattainable mandate, we made it clear we would fight this unilateral action any way we could, and this day could not have happened soon enough. President Trump has once again put families and jobs ahead of left-wing ideology and should be commended for his action."

Senate Minority Leader Chuck Schumer

"President Trump’s decision to withdraw from the Paris Climate Agreement is a devastating failure of historic proportions," said Schumer. "Future generations will look back on President Trump’s decision as one of the worst policy moves made in the 21st century because of the huge damage to our economy, our environment and our geopolitical standing. Pulling out of the Paris agreement doesn’t put America first, it puts America last in recognizing science, in being a world leader and protecting our own shore line, our economy and our planet. It’s now crystal clear President Trump is comfortable both ceding the moral high ground and the economic upper hand to countries like China, and endangering the future of our planet.

Former Vice President Al Gore

Gore called the decision an "indefensible action" that "undermines America’s standing in the world and threatens to damage humanity’s ability to solve the climate crisis in time."

"But make no mistake: if President Trump won’t lead, the American people will," Gore said. He called on "civic leaders, mayors, governors, CEOs, investors and the majority of the business community" to take up the challenge.

"We are in the middle of a clean energy revolution that no single person or group can stop," Gore said. "President Trump’s decision is profoundly in conflict with what the majority of Americans want from our president; but no matter what he does, we will ensure that our inevitable transition to a clean energy economy continues."

New York Gov. Andrew Cuomo

Cuomo called the decision "reckless," adding that it will have "devastating repercussions" for the planet.

"New York State is committed to meeting the standards set forth in the Paris Accord regardless of Washington's irresponsible actions," Cuomo said. "We will not ignore the science and reality of climate change, which is why I am also signing an Executive Order confirming New York's leadership role in protecting our citizens, our environment, and our planet."

Former New York City Mayor Michael Bloomberg

"Americans are not walking away from the Paris Climate Agreement. Just the opposite – we are forging ahead... As a sign of our commitment, Bloomberg Philanthropies, in partnership with others, will make up the approximately $15 million in funding that the U.N.’s Climate Secretariat stands to lose from Washington. Americans will honor and fulfill the Paris Agreement by leading from the bottom up – and there isn’t anything Washington can do to stop us.”

Boston Mayor Martin J. Walsh

Walsh called the move to withdraw from the Paris agreement "irresponsible" and "a setback."

"This damages our nation's reputation as an international leader and puts future generations at risk to the threat of climate change," he said. "Boston will not standby given what's at stake."

Pittsburgh Mayor Bill Peduto

California Gov. Jerry Brown

The governor of California said Trump has "chosen the wrong course."

"California will resist this misguided and insane course of action," said Brown. "Trump is AWOL but California is on the field, ready for battle."

Washington Gov. Jay Inslee

The governor of Washington said Trump's announcement will leave "full responsibility of climate action" to states and cities.

"While the president’s actions are a shameful rebuke to the work needed to protect our planet for our children and grandchildren, states have been and will continue to step up," said Inslee.

New York City Mayor Bill de Blasio

The mayor of New York City also vowed to commit to the Paris climate agreement, saying New Yorkers are "already experiencing hotter summers, more powerful storms and rising seats, which disproportionately affect already vulnerable communities."

"President Trump can turn his back on the world, but the world cannot ignore the very real threat of climate change," de Blasio said. "This decision is an immoral assault on the public health, safety and security of everyone on this planet."

Massachusetts Gov. Charlie Baker

"While the decision by the Trump-Pence Administration to withdraw from the Paris Climate Agreement is disappointing, the Commonwealth is committed to working with our partners around the nation and world to reduce carbon emissions," said Baker. "Despite today’s announcement, Massachusetts is aggressively working to exceed the goals of the Paris Agreement on the state level, while growing our economy through clean energy innovation and environmental stewardship. In Massachusetts and around the world, climate change is a shared reality and our ability to rise and respond to this challenge will shape future generations."

West Virginia Sen. Joe Manchin

"While I believe that the United States and the world should continue to pursue a cleaner energy future, I do not believe that the Paris Agreement ensures a balance between our environment and the economy," said Manchin. "To find that balance, we should seek agreements that prioritize the protection of the American consumer as well as energy-producing states like West Virginia, while also incentivizing the development of advanced fossil energy technologies."

Texas Sen. Ted Cruz

Kentucky Sen. Rand Paul

Connecticut Sen. Chris Murphy

Maine Sen. Susan Collins

Business Leaders and Businesses

Facebook CEO Mark Zuckerberg

Apple CEO Tim Cook

CEO of SpaceX Elon Musk

Chairman and CEO of General Electric Jeff Immelt

Salesforce CEO Mark Benioff

Google CEO Sundar Pichai

Microsoft

"We believe that climate change is an urgent issue that demands global action," said Microsoft President and Chief Legal Officer Brad Smith. "We remain steadfastly committed to the sustainability, carbon and energy goals that we have set as a company. Our experience shows us that these investments and innovations are good for our planet, our company, our customers and the economy. While we are disappointed that the White House has chosen to exit the Paris Agreement, we will continue our work to support a resilient, sustainable low-carbon future for everyone on the planet."

Mars Incorporated

"Mars stands by the Paris Climate Agreement," said Mars CEO Grant Reid. "We remain committed to work with all governments and our supply chain partners around the world to achieve the carbon reduction targets the planet needs."

Shell

Foreign entities

France, Germany and Italy

In a joint statement, the heads of state for France, Germany and Italy said they "take not with regret the decision by the United States of America to withdraw from the universal agreement on climate change."

"The Paris Agreement remains a cornerstone in the cooperation between our countries, for effectively and timely tackling climate change and for implementing the 2030 Agenda sustainable development goals," the statement read. "We deem the momentum generated in Paris in December 2015 irreversible and we firmly believe that the Paris Agreement cannot be renegotiated, since it is a vital instrument for our planet, societies and economies."

The United Nations

Stéphane Dujarric, spokesman for the secretary-general of the U.N., said the decision to withdraw is a "major disappointment for global efforts to reduce greenhouse gas emissions and promote global security" and that it is "crucial that the United States remains a leader on environmental issues."

"The Paris Agreement was adopted by all the world’s nations in 2015 because they recognize the immense harm that climate change is already causing and the enormous opportunity that climate action presents," Dujarric said. "It offers a meaningful yet flexible framework for action by all countries."

Environmental groups

Green America

In a statement, nonprofit Green America denounced the decision to reject the Paris Climate Agreement.

"This move is exactly the wrong direction for our nation and world," said Fran Teplitz, Green America’s executive co-director. "There is tremendous urgency –- for the sake of our communities, human health, the environment, and the economy –- to expedite the transition to a clean energy economy that works for everyone. Trump’s decision to support the fossil fuel industry over the interest of people and the planet is an historic failure."

Environment Entrepreneurs

Withdrawing from the Paris Agreement will hurt American workers and businesses, said Environment Entrepreneurs, which describes itself on its website as a nonpartisan group of business owners, investors and others who advocate for policies that are good for the economy and good for the environment.

"President Trump is ceding American leadership and sending a message to clean energy investors to look elsewhere for opportunities," said Bob Keefe, executive director of Environmental Entrepreneurs. "It will inflict real financial pain on millions of American workers who earn their paychecks every day in the clean energy and clean transportation sectors. This action ignores strong public support for the agreement voiced by American businesses, big and small, in every state and every industry."

Sierra Club

The Sierra Club, a New York City-based nonprofit, said that generations from now Americans will look back at Trump’s decision as “one of the most ignorant and dangerous actions ever taken by any President.”

“Trump’s decision to ignore the vast majority of the American public and the scientific community will harm our country, costing us lives, jobs and our role as a world leader,” said Sierra Club Executive Director Michael Brune. “Trump has isolated our country on the world stage, ceding our leadership position and our economic advantage on clean energy to India and China, and justifying it all by chanting a slogan from a baseball hat.