US President Donald Trump has rolled back all of the scientific measures taken by the United States to reduce global warming during the presidency of former President Obama.

This scientific discovery, known as the "Endangered Findings," was released during the presidency of former President Obama and lists several greenhouse gas emissions that pose a threat to public health.

The scientific discovery served as the basis for federal legislation, particularly to reduce emissions from vehicles.

The White House called the repeal of the scientific discovery "the largest legislative blunder in American history."

Environmental groups have threatened to challenge the decision in court, calling it the biggest rollback ever attempted on climate change.

Speaking in the Oval Office on Thursday, President Trump called the 2009 directive "one of the most devastating policies of the Obama administration and one that has severely damaged the American auto industry, resulting in significant price increases for American consumers."

The Republican president, speaking about the Democrats' climate agenda, said, "This strict law has become the legal basis for a new fraud in the name of climate change. The biggest fraud in history."