WASHINGTON — Republicans deleted a reference to a discredited FBI informant in a letter they sent on Tuesday to a potential witness in their impeachment inquiry against President Joe Biden.

Republican interview request letters typically spell out the basis for their investigation, including with a paragraph describing a credible confidential human source’s conversations with a Ukrainian gas company executive about bribing Biden.

The Justice Department last week said the informant, a U.S. citizen named Alexander Smirnov, made up the allegation, and now Republicans appear to be striking any mention of it from their impeachment correspondence.

On Tuesday, House Judiciary Committee Chair Jim Jordan (R-Ohio) and House Oversight Committee Chair James Comer (R-Ky.) included the paragraph about the informant in an interview request letter to former State Department official Amos Hochstein. An hour later, according to a Democratic House aide, the chairman sent another version of the same letter, but without the paragraph about the informant. HuffPost reviewed both versions of the document.

An aide to the impeachment inquiry said the letter had been drafted prior to the indictment and that the request still stands.

The informant’s false information supported the main corruption allegation Republicans have pursued against Biden, namely that as vice president, in 2015 and 2016, he pushed out a Ukrainian prosecutor in order to protect Burisma, a Ukrainian gas company that employed his son on its board.

Current and former State Department officials, including Hochstein, have repeatedly debunked the Biden Burisma story, explaining during hours of testimony in 2019 and 2020 that ousting the prosecutor reflected a broad consensus within the State Department, as well as among European allies, that the prosecutor was corrupt.

But last year Republicans obtained and released a raw FBI file, from June 2020, in which Smirnov’s handler described Smirnov’s account of conversations with Burisma executive Mykola Zlochevsky about bribing Hunter and Joe Biden $5 million each.

As Republicans put it in their many letters requesting interviews, “According to this confidential human source, who has been described as ‘highly credible,’ Burisma executives hired Hunter Biden to ‘protect us, through his dad, from all kinds of problems.’”

Smirnov told his FBI handler that Zlochevsky said he’d used secret channels to send the money and that it would take investigators years to put the pieces together. Using subpoenas, Republicans have sifted through thousands of pages of the president’s son’s and brothers’ bank records in search of the nonexistent bribes.

Smirnov’s credibility did not come into doubt until prosecutors followed up with him last year in an effort to confirm his report from 2020, though Republicans did caution that one of his claims ― that Zlochevsky, who is not known as an English speaker, recorded conversations with the Bidens ― might be untrue.

Comer has said despite losing their best piece of corroborating evidence against the Bidens, the impeachment inquiry will carry on, with a focus on Joe Biden’s unproven involvement in his son’s business deals.

Lawmakers will interview James Biden, the president’s brother, on Wednesday, and Hunter Biden will sit for a deposition next week. It’s unclear if articles of impeachment against the president will ever get a vote in the House of Representatives.