Rod Rosenstein, the US Attorney General who oversaw the investigation into the alleged Russian interference, is expected to withdraw by mid-March, US media reports said.
Last month, reports revealed that Rosenstein was considering resigning after new Attorney General William Barr took office.
The appointment of Mr. Barr was confirmed by the Senate last week.
Mr. Rosenstein has often been criticized by President Donald Trump.
A Justice Department representative quoted Reuters as saying that Rosenstein's decision was not related to new claims that he had once suggested secretly registering Mr. Trump.
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In an interview on television on Sunday, former FBI interim leader Andrew McCabe said talks had been held in 2017 to invoke the 25th amendment to the US Constitution that could revoke a president deemed unfit.
He stated that Mr. Rosenstein had discussions about the number of cabinet members and others needed to invoke this clause.
President Trump reacted furiously to the interview, tweeting "illegal and treacherous" behavior and an "illegal coup d'etat".
The White House said McCabe, who was fired last year for allegedly lied to government investigators, had "no credibility".
The Department of Justice said McCabe's story was "inaccurate and factually inaccurate".
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Mr. Rosenstein previously denied having such discussions on the invocation of the amendment, calling the reports "inaccurate and factually inaccurate".
The investigation of the Attorney General Robert Mueller regarding the alleged investigator of Russian interference in the 2016 presidential election was entrusted to him following the challenge of the Former Attorney General Jeff Sessions.
However, following the ouster of Mr. Sessions in November, his replacement, Matthew Whitaker, resumed the investigation, refusing to recuse himself despite criticisms he had previously made to the public about the subject. # 39; investigation. Mr. Rosenstein continued to help supervise the investigation.