President-elect Donald Trump has nominated vaccine sceptic Robert F Kennedy Jr to head the United States federal health agency.
Trump confirmed the pick on the social media platform X, formerly Twitter.
Mr Kennedy ran unsuccessfully for the Democrats' ticket, and then as an independent presidential candidate before he ended his bid and allied himself with the Trump campaign.
He is a former environmental lawyer who has expressed anti-vaccine views and flagged advising that fluoride be removed from America's water supplies.
He is the nephew of Democratic president John F Kennedy, and the son of former attorney-general and aspiring presidential nominee Robert F Kennedy, both of whom were assassinated in the 60s.
Trump has nominated Mr Kennedy to serve in his cabinet as secretary of the Department of Health and Human Services.
"For too long, Americans have been crushed by the industrial food complex and drug companies who have engaged in deception, misinformation, and disinformation when it comes to public health," Trump's tweet read.
"The safety and health of all Americans is the most important role of any administration, and HHS will play a big role in helping ensure that everybody will be protected from harmful chemicals, pollutants, pesticides, pharmaceutical products, and food additives that have contributed to the overwhelming health crisis in this country."
During the campaign, Trump said several times he wanted Mr Kennedy to "go wild" on public health.
Mr Kennedy has previously said on social media that one of his first moves in office would be to advise fluoride be removed from US water systems.
Trump later said he had not discussed that specific policy with Mr Kennedy but that "it sounds OK to me".
Mr Kennedy has been a leader in the anti-vaccine movement, and his views have been criticised by public health experts as dangerous.
His rhetoric and prominence have increased since the COVID-19 pandemic.
He also runs an anti-vaccine charity called Children's Health Defense.
Not all of his views are extreme. For example, he is a staunch advocate for tighter regulations about the chemicals put in food and used during farming.
Mr Kennedy will still need to be confirmed by the US Senate — a process all cabinet positions are subjected to.
If that happens, he would oversee the operations of the country's largest health programs like the Affordable Care Act, Medicare and Medicaid.
Paul Offit, a professor at the Children's Hospital of Philadelphia and the University of Pennsylvania, and a specialist in infectious diseases and immunology, spoke to the ABC's RN Breakfast program earlier this week where he described Mr Kennedy as a "science denialist" and a "conspiracy theorist".
"He continues to spout lies, and he is always unrepentant," Dr Offit said.
"For example, he continues to say the measles-mumps-rubella vaccine causes autism even though 18 studies done in seven countries on three continents have shown that's not true.
"He just has these non-falsifiable beliefs that he holds with the conviction of a religious belief."
Just before the election, Trump's transition co-chair Howard Lutnick was quoted on CNN saying Mr Kennedy would not be put in charge of HHS.
The announcement came after several busy days of nominations from the Trump camp, which has been war-gaming what the next White House will look like from the president-elect's private Palm Beach club, Mar-a-Lago.
On Wednesday, local time, Trump announced firebrand Republican Matt Gaetz was his pick for attorney-general, in a move that sparked outrage from Democrats and even scepticism from within his own party.
There are also question marks over whether Trump's nominee for the role of defence secretary, Pete Hegseth, will be confirmed.
Other recently announced nominations include former Missouri solicitor-general John Sauer for US solicitor-general; former representative Doug Collins for secretary of veterans affairs, Todd Blanche for deputy attorney-general, and corporate lawyer Jay Clayton for Attorney for the Southern District of New York.