US President Joe Biden signed a series of actions Wednesday to combat climate change, saying they will restore “scientific integrity and evidence-based policymaking” across the U.S. government.

A week into his presidency, the new U.S. leader called climate change an “existential threat,” according to VOA.“It’s time to act,” he said at the White House. “We can’t wait any longer. We know what to do. We’ve just got to do it.”In advance of Biden signing three orders, the White House said the actions would allow the U.S. to achieve “a carbon pollution-free power sector by 2035 and puts the United States on an irreversible path to a net-zero economy by 2050.”According to VOA, Biden signed a memorandum on scientific integrity that the White House said would “protect scientists from political interference and ensure they can think, research, and speak freely to provide valuable information and insights to the American people.”Additionally, Biden reestablished the President’s Council of Advisors on Science and Technology, a panel that former President Donald Trump left vacant for much of his White House tenure.Biden said the orders to combat climate change will make the issue an “essential element of U.S. foreign policy and national security.”“The United States will exercise its leadership to promote a significant increase in global ambition,” the White House said, adding that Wednesday’s climate change orders “makes clear that both significant short-term global emission reductions and net-zero global emissions by mid-century — or before — are required to avoid setting the world on a dangerous, potentially catastrophic, climate trajectory.”

Shortly after his Jan. 20 inauguration, Biden announced the U.S. would rejoin the 2016 international Paris climate change pact and named former Secretary of State John Kerry to serve as his climate envoy.