Robert F Kennedy Jr is to reveal what he claims are the “causes” of autism at a news conference in September.

Donald Trump’s US health secretary launched an inquiry into the root of the neurological condition, which is widely believed to be at least partially influenced by genetics.

Speaking during a lengthy cabinet meeting on Tuesday, Mr Kennedy said: “We’re finding interventions, certain interventions now that are clearly, almost certainly causing autism.

“And we’re going to be able to address those in September.”

Mr Trump responded by citing a rise in autism diagnoses, adding: “There has to be something artificially causing this, meaning a drug or something... we’re going to do some things.”