Hunter Biden, the son of President Joe Biden, is threatening “imminent” litigation against Fox News over allegations the right-wing news network has defamed him, used his copyrighted material without permission and unlawfully published hacked, intimate photos of him, his lawyers said in a letter to the outlet's attorneys last week.

The letter, shared on Monday with Spectrum News by Biden’s attorney Tina Glandian, is the latest attempt by the businessman and artist to fight back against the U.S. right’s attempts to use his career and reputation to attack his father, who is pursuing reelection this fall.

“For the last five years, Fox News has relentlessly attacked Hunter Biden and made him a caricature in order to boost ratings and for its financial gain,” Glandian said in an emailed statement. “The recent indictment of FBI informant [Alexander] Smirnov has exposed the conspiracy of disinformation that has been fueled by Fox, enabled by their paid agents and monetized by the Fox enterprise. We plan on holding them accountable.”

Smirnov, a dual Israeli-U.S. citizen and longtime federal informant, was charged earlier this year for lying to his FBI handler that the Ukrainian energy company Burisma paid Biden and his father, then the vice president, $5 million each around 2015. That claim, which federal law enforcement now says was false and allegedly motivated by biases against the Bidens, was trumpeted by House Republicans and inspired their impeachment inquiry into the elder Biden. (The probe has yet to yield any evidence of criminal wrongdoing by the president.)

In the letter, Glandian notes Fox News host Maria Bartiromo’s weekday and Sunday shows referenced Smirnov’s false claims 219 times in 2023. Another Fox News host, Sean Hannity, mentioned the now-debunked allegations in 28 monologues at the top of his show in 2023. In preparation for the lawsuit, Glandian is demanding Fox News preserve all communications and documents connected to Biden to and from Hannity, Bartiromo and other Fox News hosts, including primetime hosts Jesse Watters and Laura Ingraham, dating back to Jan. 1, 2019.

Biden’s attorneys are demanding retractions and corrections be placed on every online story referencing the bribery allegations and that each of the on-air hosts inform their audiences that “they have been sharing a debunked allegation from a source who has been federally indicted.”

Fox News was given an April 26 deadline to respond to the letter and its demands, but did not respond, according to Glandian. On Tuesday morning, the sent out a statement to the media.

“Hunter Biden’s lawyers have belatedly chosen to publicly attack Fox News’ constitutionally protected coverage regarding their client. Mr. Biden is a public figure who has been the subject of investigations by both the Department of Justice and Congress, has been indicted by two different US Attorney’s Offices in California and Delaware, and has admitted to multiple incidents of wrongdoing," the network said in a statement. "Consistent with the First Amendment, Fox News has accurately covered these highly publicized events as well as the subsequent indictment of an FBI informant who was the source of certain claims made about Mr. Biden.”

Glandian noted specifically that an FBI official wrote in a May 10, 2023, public letter to House Oversight Committee Chair James Comer, R-Ky., that the existence of Smirnov’s allegations did not necessarily mean investigators believed it. That public warning should have tempered Fox News’ coverage of the allegations, Glandian wrote. Instead, the network continued to run stories emphasizing the credibility of the yet to be identified source.

“Information from confidential human sources is unverified and, by definition, incomplete,” wrote Christopher Dunham, the FBI’s acting assistant director of congressional affairs. “The mere existence of such a document would establish little beyond the fact that a confidential human source provided information and the FBI recorded it. Indeed, the FBI regularly receives information from sources with significant potential biases, motivations, and knowledge, including drug traffickers, members of organized crime, or even terrorists.”

Smirnov, who prosecutors said claims connections to Russian intelligence, was ordered to remain imprisoned while he awaits trial because of those alleged connections.

The threatened lawsuit -- which Glandian indicated may also center on the usage of hacked, graphic photos taken from Biden’s personal devices and the usage of Biden’s image generally to produce a mock trial streaming show -- comes in the wake of Fox News settling a $787.5 million lawsuit a year ago this month with Dominion Voting Systems. The voting company sued over claims Fox News damaged its reputation by promoting and spreading false conspiracy theories that its equipment swapped votes for former President Donald Trump in favor of Biden’s father in the 2020 general election. Fox News is also battling a multibillion dollar defamation lawsuit from Smartmatic, another voting machine company with similar complaints.

Smartmatic settled a similar lawsuit with the right-wing news organization One America News Network earlier this month. And on Monday, OAN retracted a March 27 article that leveled baseless allegations about Trump’s former lawyer Michael Cohen and Stormy Daniels, the adult film actress at the center of Trump’s hush money criminal trial.

Biden has taken an increasingly confrontational tact at pushing back on his political and legal troubles, including publicly feuding with House Republicans investigating him and his father. But he also faces two criminal prosecutions, including an impending trial in June on federal gun charges in Delaware for allegedly lying about his personal drug use in October 2018 on a form to buy a gun that he kept for about 11 days.

He faces separate tax counts in Los Angeles alleging he failed to pay at least $1.4 million in taxes over three years while living an “extravagant lifestyle,” during his days of using drugs. Biden’s attempts to delay or dismiss the prosecutions have so far been fruitless.

The Associated Press contributed to this report.