Dr Anthony Fauci, the US’s top infectious disease expert, will step down from the federal government at the end of the year.
The 81-year-old served as director of the National Institute of Allergy and Infectious Diseases (NIAID) and chief medical adviser to President Joe Biden.
He served in the NIAID for 38 years and became the face of the nation’s COVID-19 response during the pandemic.
Dr Fauci said that he would leave both roles to “pursue the next chapter” of his career.
In a statement, Mr Biden said of his departure: “As he leaves his position in the US Government, I know the American people and the entire world will continue to benefit from Dr Fauci’s expertise in whatever he does next.
“The United States of America is stronger, more resilient and healthier because of him.”
In July, Dr Fauci said he would retire before the end of Mr Biden’s current term.
Having joined the National Institutes of Health in 1968 under Lyndon Johnson’s presidency, he was appointed as the director of the NIAID in 1984 during the AIDS epidemic.
He has since served under seven presidents, including Ronald Reagan and George W Bush.
During the coronavirus pandemic, Dr Fauci faced criticism from Donald Trump and other conservatives who objected to enforcing measures to limit the spread of COVID.
He also acquired many fans during the pandemic, with a petition to name him as People Magazine’s Sexiest Man Alive in 2020 gaining thousands of signatures.
Though Dr Fauci is leaving his government role, he made it clear on Monday that he was not retiring.
“I plan to pursue the next phase of my career while I still have so much energy and passion for my field,” he said.
Dr Fauci, who will turn 82 on 24 December, did not set an exact date for his departure.