Robert F Kennedy Jr is planning to challenge President Joe Biden for the White House in 2024.
The outspoken anti-vaccine campaigner and nephew of assassinated President John F Kennedy (JFK) has announced his bid for Democratic leader.
President Biden has indicated he will run for re-election, though he has not yet formally declared his candidacy.
Mr Kennedy filed a statement of candidacy on Wednesday with the Federal Election Commission.
The 69-year-old, who is the son of JFK's murdered brother Robert F. Kennedy, was once a bestselling author and environmental lawyer who worked on issues such as clean water.
Mr Kennedy had been long involved in the anti-vaccine movement, but the effort intensified after the coronavirus pandemic and development of the Covid-19 vaccine.
He has since emerged as one of the leading voices in the anti-vaccine movement in the US, and his work has been described by public health experts - and even members of his own family - as misleading and dangerous.
Mr Kennedy's anti-vaccine charity, Children’s Health Defense, prospered during the pandemic, with revenues more than doubling in 2020 to $6.8 million, according to filings made with charity regulators.
In 2021, he released a book called The Real Anthony Fauci, in which he accused the US’s top infectious disease doctor of assisting in “a historic coup d’etat against Western democracy”.
The book promoted unproven Covid-19 treatments such as ivermectin - which is meant to treat parasites - and the anti-malaria drug hydroxychloroquine.
Mr Kennedy has repeatedly invoked Nazis and the Holocaust when talking about measures aimed at mitigating the spread of Covid, such as mask requirements and vaccine mandates.
He has sometimes apologised for those comments, including when he suggested that people in 2022 had it worse than Anne Frank, who was a teenager when she died in a Nazi concentration camp after hiding with her family in a secret annex in an Amsterdam house for two years.
Mr Kennedy’s comments, which were made at a Washington rally in 2022, put on by his anti-vaccine non-profit group, were widely condemned as offensive and ignorant.
It was the second time since 2015 that Mr Kennedy had referred to the Holocaust while trying to sow doubt and distrust about vaccines.
Days later he apologised for his comments in a Tweet that read: “I apologize for my reference to Anne Frank, especially to families that suffered the Holocaust horrors.
“My intention was to use examples of past barbarism to show the perils from new technologies of control. To the extent my remarks caused hurt, I am truly and deeply sorry.”
Mr Kennedy has at times invoked his family’s legacy in his anti-vaccine work, including sometimes using images of President Kennedy.
His sister Kerry Kennedy, who runs Robert F. Kennedy Human Rights, the international rights group founded by their mother, Ethel, said her brother has at times removed some of the content at her request.
In an interview in 2021 she said her brother is “completely wrong on this issue and very dangerous.”
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