A top politics writer for New York magazine has taken leave at the publication after it emerged that she allegedly had a personal relationship with Robert F Kennedy Jr, a scion of the Kennedy dynasty who ran a high-profile independent campaign for the White House before endorsing Donald Trump.

Olivia Nuzzi, who has written extensive long-form pieces about US politics, including RFK Jr, violated the magazine’s standards around disclosing conflicts of interests, the publication said in a statement.

“Our Washington Correspondent Olivia Nuzzi acknowledged to the magazine’s editors that she had engaged in a personal relationship with a former subject relevant to the 2024 campaign while she was reporting on the campaign, a violation of the magazine’s standards around conflicts of interest and disclosures,” New York said.

It added: “Had the magazine been aware of this relationship, she would not have continued to cover the presidential campaign. An internal review of her published work has found no inaccuracies nor evidence of bias. She is currently on leave from the magazine, and the magazine is conducting a more thorough third-party review. We regret this violation of our readers’ trust.”

In a statement Nuzzi acknowledged the relationship but said it had not been a physical one and that it had developed after Nuzzi had written a piece about Kennedy and his quixotic and ultimately doomed run for the White House.

Nuzzi said that “the nature of some communication between myself and a former reporting subject turned personal” earlier this year.

“During that time, I did not directly report on the subject nor use them as a source,” she said. “The relationship was never physical but should have been disclosed to prevent the appearance of a conflict. I deeply regret not doing so immediately and apologize to those I’ve disappointed, especially my colleagues at New York.”

A spokesperson for RFK Jr told CNN that Kennedy “only met Olivia Nuzzi once in his life for an interview she requested, which yielded a hit piece”.

RFK Jr is the son of Robert Francis Kennedy, who was assassinated in 1968 while running for the Democratic nomination for president, almost five years after his brother and the US president, John F Kennedy, was assassinated.

RFK Jr’s 2024 independent campaign never really took off to challenge the Democrats or Republicans and his extreme stances on some issues, especially around vaccinations, did little to endear him to mainstream Americans.

Nuzzi has become a high-profile American journalist and television pundit. One of her most recent pieces included an interview with Donald Trump in which the former US president invited her to examine his ear, injured in an assassination attempt at a Pennsylvania rally. Recounting the experience, she wrote: “An ear had never appeared to have gone through less.”

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