Independent US presidential candidate Robert F Kennedy jnr plans to drop out of the race by the end of the week and endorse Republican former President Donald Trump, according to media reports.

Kennedy’s campaign announced earlier on Wednesday (US time) that he would make an address to the nation on Friday in Arizona, where he will talk about “the present historical moment and his path forward”.

An ABC News reporter said in a post on X that he asked Kennedy whether he would endorse Trump.

“I will not confirm or deny that,” Kennedy said, according to the reporter.

“We are not talking about any of that.”

Kennedy’s running mate, Nicole Shanahan, said on Tuesday that he was considering ending his campaign to join forces with Trump, who is the Republican nominee for the November 5 election.

Trump told CNN he would “certainly be open” to Kennedy playing a role in his administration if the independent candidate dropped out and endorsed him.

Kennedy, 70, the son of late Democratic politician Robert F Kennedy and nephew of the late President John F Kennedy, started his presidential campaign as a Democrat, challenging President Joe Biden for the nomination.

An environmental advocate who has spread vaccine misinformation, Kennedy has yet to qualify for the ballot in many states.

Kennedy’s support stood at 4 per cent in an Ipsos poll taken this month, down from 10 per cent the month before.