Special counsel David Weiss has indicted an FBI confidential source who provided derogatory information about President Joe Biden and his son Hunter Biden on felony false statement and obstruction charges.

Weiss indicted Alexander Smirnov, 43, on one count of making a false statement and one count of creating a false and fictitious record related to statements he made to the FBI on a document known as an FBI Form 1023.

Charging documents released on Thursday show Smirnov was a confidential source for the FBI and allegedly provided "false derogatory information about [President Biden] and [Hunter Biden] ... in 2020, after [Biden] became a presidential candidate."

Smirnov is the same person that Republicans have called "a highly credible FBI source" and have used to claim Joe Biden is corrupt, according to multiple senior congressional sources.

However, House Oversight Committee Chairman James Comer has since released a statement saying, in part, that Smirnov's charges do not undermine the GOP impeachment inquiry into Joe Biden.

However, the FBI source and his claims have repeatedly been raised by Republicans as they push forward with an impeachment inquiry into the president, but now the FBI is calling the source a liar.

The allegations of Biden corruption spilled into public nearly a year ago, when Sen. Chuck Grassley, an Iowa Republican, took the extraordinary step of releasing the confidential FBI informant's unverified claim that, years ago, the Biden family "pushed" a Ukrainian oligarch to pay them $10 million.

The claim -- which Democrats and the White House immediately denied -- has since been cited by congressional Republicans to justify their impeachment inquiry.

"The impeachable offenses, I think the key thing is in Burisma," House Judiciary Committee Chairmen Jim Jordan told reporters in December, referring to the bribery claim.

In the wake of Smirnov being charged, Comer said in his statement on Thursday that "to be clear, the impeachment inquiry is not reliant on the FBI’s FD-1023 [that included Smirnov's allegation]."

The Republican-led probe "is based on a large record of evidence, including bank records and witness testimony, revealing that Joe Biden knew of and participated in his family’s business dealings," Comer maintained. (The president rejects that.)

Hunter Biden's attorney Abbe Lowell responded to Smirnov's charges in his own statement, saying, “For months we have warned that Republicans have built their conspiracies about Hunter and his family on lies told by people with political agendas, not facts."

"We were right and the air is out of their balloon," Lowell said.

On Thursday evening, a spokesperson for Weiss said Smirnov was "ordered detained pending a detention hearing" that takes place next Tuesday in Las Vegas. ABC News wasn't immediately able to locate a legal representative for Smirnov.

Smirnov allegedly reported to an FBI agent in March 2017 that he had a phone call with the owner of Burisma, a Ukrainian energy company, and noted Hunter Biden was at the time a member of Burisma's board.

Three years later, Smirnov allegedly made false statements in describing two meetings in 2015 or 2016 in which executives associated with Burisma told him they had hired Hunter Biden to "protect us, through his dad, from all kinds of problems."

According to federal authorities, Smirnov further said the executives paid $5 million each to Hunter Biden and Joe Biden while the latter was in office as vice president, so that Hunter Biden "will take care of all those issues through his dad," referring to the then-criminal investigation being conducted by the then-Ukrainian prosecutor general into Burisma.

Those events were fabrications, Weiss alleged in his new indictment.

Instead, Smirnov had only contacted the Burisma executives in 2017 after the end of Joe Biden's time as vice president and after the Ukrainian prosecutor general had already been fired, according to the indictment.

"The indictment alleges that the [Smirnov] transformed his routine and unextraordinary business contacts with Burisma in 2017 and later into bribery allegations against [President Biden] after expressing bias against [Biden] and his presidential candidacy," Weiss' office said in their statement announcing the charges.

Smirnov was again interviewed by FBI agents in September 2023, the indictment says, and he allegedly repeated earlier false claims and also changed his story to promote "a new false narrative after he said he met with Russian officials."

Smirnov was arrested at Harry Reid International Airport in Las Vegas on Wednesday after arriving to the U.S. from overseas, the Department of Justice said. He was scheduled to make his initial appearance Thursday.

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

ABC News' Justin Fishel and John Parkinson contributed to this report.