EXCLUSIVE: Dr. Scott Atlas, President Trump’s special adviser on the coronavirus pandemic, formally resigned from his post on Monday, Fox News has learned.

Atlas, who spoke with the president on Monday, joined the administration in August, and was considered a Special Government Employee (SGE), serving a 130-day detail. Atlas’ role is set to expire this week.

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Fox News exclusively obtained Atlas’s resignation letter Monday, which was dated Dec. 1. In it, Atlas touted the Trump administration's work on the coronavirus pandemic, while wishing "all the best" to the incoming Biden administration.

“I am writing to resign from my position as Special Advisor to the President of the United States,” Atlas said, thanking him for “the honor and privilege to serve on behalf of the American people.”

“I worked hard with a singular focus—to save lives and help Americans through this pandemic,” Atlas wrote, adding that he “always relied on the latest science and evidence, without any political consideration or influence.”

“As time went on, like all scientists and health policy scholars, I learned new information and synthesized the latest data from around the world, all in an effort to provide you with the best information to serve the greater public good,” Atlas wrote. “But, perhaps more than anything, my advice was always focused on minimizing all the harms from both the pandemic and the structural policies themselves, especially to the working class and the poor.”

Atlas, who had been criticized throughout his tenure for calling for a reopening, and saying that lockdowns are “extremely harmful” to Americans, said that “although some may disagree with those recommendations, it is the free exchange of ideas that lead to scientific truths, which are the very foundation of a civilized society.”

“Indeed, I cannot think of a time where safeguarding science and the scientific debate is more urgent,” Atlas said.

Atlas went on to tout his work at the White House, and his work with “several selfless colleagues in designing specific policies to heighten protection of the vulnerable while safely reopening schools and society.”

Atlas pointed to their efforts in increasing and prioritizing “extra personal protective equipment and tens of millions of extra tests to nursing and assisted living facilities,” as well as implementing “more frequent monitoring updates using clinical guidelines to intensify testing,” and instituting outreach to independent seniors in communities.

“We also successfully designed rational guidelines for safely opening schools, a strategic use of the newly developed testing program, and a national stockpile of drugs for future crises,” Atlas wrote.

Shifting to lockdowns he has warned against throughout his tenure, Atlas said they “identified and illuminated early on the harms of prolonged lockdowns, including that they create massive physical health losses and psychological distress, destroy families and damage our children.”

“And more and more, the relatively low risk to children of serious harms from the infection, the less frequent spread from children, the presence of immunologic protection beyond that shown by antibody testing, and the severe harms from closing schools and society are all being acknowledged,” Atlas added.

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Atlas also touted Operation Warp Speed, and the team that “delivered on our promised timelines for new drugs and vaccines.”

“I congratulate you for your vision, and also congratulate the many who did the exemplory work—we know who they are, even though their names are not those familiar to the public,” Atlas wrote.

Atlas went on to wish the best to the incoming Biden Administration.

“I sincerely wish the new team all the best as they guide the nation through these trying, polarized times,” Atlas wrote. “With the emerging treatments and vaccines, I remain highly optimistic that America will thrive once again and overcome the adversity of the pandemic and all that it has entailed.”

Atlas, during his tenure, sparred with members of the White House Coronavirus Task Force.

Over the summer, Centers for Disease Control and Prevention Director Robert Redfield reportedly criticized Atlas, claiming that “everything he says is false.”

Atlas defended his record and his expertise, and maintained that all of his advice to the president was based on the “current science.”

“I was asked to be an adviser on the coronavirus pandemic to the president of the United States and I was asked to do that because I have a 25-year career at top, elite medical centers, as a doctor and in patient care,” Atlas told Fox News this summer. “I also have a 15-year career in public policy, working on health care policy and integrating my medical knowledge in policy.”

Atlas added that before his arrival to the White House this summer, “that expertise had not been present.”

“I am here because I understand how to translate complex medical science into plain English for the president of the United States and for everyone else in the White House, and derive appropriate public policy from that information,” Atlas said at the time, adding that there is a “false belief” that one “has to be a public health official to understand the facts about the pandemic.”

“The way I advise the president is perfectly consistent with the most appropriate strategy for dealing with this pandemic,” he said. “One, target diligent protection of the high risk and vulnerable populations, and two, open up schools and society.”

Meanwhile, as for a coronavirus vaccine, the Trump administration said deliveries of the vaccine will begin as early as this week, and would be available first for front-line workers, medical personnel and senior citizens.

The president, on Thanksgiving, argued that his opponent, President-elect Joe Biden, should not be given credit for the vaccines, which he referred to as a "medical miracle" before repeating claims of voting irregularities in the 2020 election.

"Joe Biden failed with the swine flu, H1N1, totally failed with the swine flu," Trump said. "Don't let him take credit for the vaccines because the vaccines were me and I pushed people harder than they've ever been pushed before and we got that approved and through and nobody's ever seen anything like it." 

Trump's comments came ahead of a Dec. 10 meeting, where regulators at the Food and Drug Administration will review Pfizer's request for an emergency use authorization for its vaccine developed with BioNTech. 

The latest trial data for Pfizer and BioNTech's vaccine, unveiled earlier this month, showed it was 90% effective.

In addition, Moderna said its vaccine is 94.5% effective in preventing COVID-19. AstraZeneca also reported preliminary results that showed its vaccine efficacy ranged from 62% to 90%, depending on the dosage amount given to participants.

According to Health and Human Services Secretary Alex Azar, the vaccines will be “shipped” within 24 hours of FDA approval and then it would be up to “nursing homes, hospitals, and pharmacies to get that dispensed.” 

“It really could be within days of FDA approval we’ll start seeing vaccines in people’s arms which is frankly incredible,” Azar said Monday.

The United States has reported more than 13.5 million cases of COVID-19 since the onset of the pandemic, and more than 267,000 deaths.