The United States has submitted formal notification of its withdrawal from the United Nations (UN) global climate agreement, aka Paris Agreement, effective one year from now, Trump administration officials said Monday.

The announcement came more than two years after President Trump, who has called climate change a "hoax" perpetrated by China, said the United States would withdraw from the global climate agreement.

"President Trump made the decision to withdraw from the Paris Agreement because of the unfair economic burden imposed on American workers, businesses, and taxpayers by U.S. pledges made under the agreement," said Secretary of State Mike Pompeo. "The United States has reduced all types of emissions, even as we grow our economy and ensure our citizens' access to affordable energy...

"The U.S. approach incorporates the reality of the global energy mix and uses all energy sources and technologies cleanly and efficiently, including fossil fuels, nuclear energy, and renewable energy. In international climate discussions, we will continue to offer a realistic and pragmatic model -- backed by a record of real world results -- showing innovation and open markets lead to greater prosperity, fewer emissions, and more secure sources of energy. We will continue to work with our global partners to enhance resilience to the impacts of climate change and prepare for and respond to natural disasters."

The climate pact was reached by more than 190 countries in December 2015 during the Conference of Parties to the UN Framework Convention on Climate Change. Participating nations are required to submit emissions reduction plans and review those plans every five years to lay the foundation for keeping a global temperature rise below 2 C (3.6 F) above pre-industrial levels.

In signing the accord, President Obama had pledged a 26-28% reduction in U.S. emissions by 2025, underpinned by federal mandates to reduce emissions from the electricity, transportation and fossil fuel sectors.

Because the accord was structured as an "agreement" rather than a treaty, it did not require congressional approval. President Obama signaled the United States would join in a short letter to the UN dated Aug. 29, 2016. A clause in the Paris agreement did not allow Trump to write his letter to the UN until three years after the pact is in force, i.e. Nov. 4, 2019. It then would take another year before the United States would be able to withdraw. That would put the official withdrawal date at Nov. 4, 2020, one day after the next presidential election.

Among those who have urged Trump to keep the United States in the Paris Agreement have been scientists, NASA and academia, as well as top U.S. companies, including tech leaders and many leading U.S. natural gas and oil producers, including No. 1 North American natural gas producer ExxonMobil Corp. BP plc and Royal Dutch Shell plc, each based in Europe, and Houston-based ConocoPhillips also had lobbied to remain in the accord.

Despite the federal government's retreat from the global agreement, states across the nation and private companies continue to advance ambitious climate protection plans. Amazon, the online retail giant that delivers 10 billion items annually and is a leading U.S. employer, said recently it will work to achieve net-zero carbon across its operations by 2040, 10 years earlier than a target as called for in the Paris Agreement.

Maine Democratic Gov. Janet Mills pledged the same week that her state's economy would be carbon-neutral by 2045. She issued an executive order directing her recently formed climate council to make recommendations to meet that goal by late next year. The announcements are the latest in a series from other cities, states, companies and utilities across the country aiming to curb emissions, produce more energy with alternative resources and reduce fossil fuel consumption.

"Donald Trump is the worst president in history for our climate and our clean air and water. Long after Trump is out of office, his decision to withdraw the United States from the Paris Agreement will be seen as a historic error," said Sierra Club’s Michael Brune, executive director. "Trump has once again demonstrated that he is more interested in catering to the interests of the world's worst polluters than he is in listening to the American people."