According to US prosecutors, Alexander Smirnov, a former FBI informant charged with providing false information about President Joe Biden and his son Hunter, has close ties to Russian intelligence at a high level.

The Department of Justice presented these accusations against the 43-year-old Smirnov in recent filings related to the case on Tuesday.

Smirnov stands accused of fabricating claims that bribes were funneled to the Bidens through the Ukrainian energy company Burisma, and he was formally charged last week for making false statements to the FBI.

His assertions were allegedly part of a broader Republican campaign to impeach President Biden. Smirnov was apprehended in Las Vegas, Nevada, upon his return from an overseas trip, as stated by the Justice Department.

Prosecutors had sought to detain Smirnov, who holds dual US-Israeli citizenship, without bail, citing his lack of ties to Las Vegas but his connections with Russian intelligence agencies.

Nonetheless, US Magistrate Judge Daniel Albregts granted his release under GPS monitoring until trial, with the condition that he remain in Clarke County, Nevada, and refrain from seeking a new passport.

Smirnov, who had been housed at a detention center in Pahrump, located an hour from Las Vegas, since his arrest, left court without addressing reporters.

The Justice Department revealed that Smirnov had disclosed his intelligence contacts to his FBI handler, indicating his potential use of these "extensive and extremely recent" connections to leave the United States. Additionally, prosecutors alleged in court documents filed on Tuesday that Smirnov had falsely declared possessing only $1,500 in cash and $5,000 in a bank account, while he had access to approximately $6 million in liquid assets.

"The fact that Smirnov misrepresented his assets alone should cause Smirnov to be detained because it shows that, at the first opportunity, he did not provide true and complete information to pretrial services," the filing says.

In December 2023, the legal filing says, Mr. Smirnov attended an overseas meeting with "a high-ranking member of a specific Russian foreign intelligence service".

Mr Smirnov told his FBI handler that he learned Russian intelligence had intercepted "several" phone calls made at a certain hotel by prominent US people, according to the justice department. Neither the hotel nor its location is specified.

Mr Smirnov allegedly said the eavesdropped recordings could be used as "kompromat" (compromising material) during the 2024 election campaign.

He was charged by Special Counsel David Weiss - who has overseen the investigation of Hunter Biden - with providing "false derogatory information" to the FBI about the president and his son in June 2020.

Prosecutors allege that Mr Smirnov was motivated by his dislike of the president.

If convicted, he faces a maximum of 25 years in prison.

In a separate court filing on Tuesday, Hunter Biden's attorneys sought to have federal tax charges dismissed, arguing that he was the victim of politically motivated "selective and vindictive prosecution".

Additionally, the filings argue that the prosecutors' assertions that the younger Mr Biden lived a "lavish" and "extravagant" lifestyle were "irrelevant and prejudicial" to the case.

Noted