Special counsel Robert Mueller is not investigating Attorney General Jeff Sessions for perjury or for making false statements to Congress about his contacts with Russians, a lawyer for Sessions said Wednesday.

That extraordinary statement by Sessions' attorney came as a news report said that Sessions had been the subject of a criminal investigation over possibly misleading statements to Congress — a probe that was originally being overseen by then-FBI Deputy Director Andrew McCabe.

Sessions fired McCabe on Friday for McCabe's alleged "lack of candor" on multiple occasions.

McCabe's termination was recommended by the FBI's Office of Professional Responsibility after the Justice Department's inspector general found that McCabe showed a lack of candor about his decision to allow FBI officials to talk to reporters during a probe of the Clinton Foundation.

McCabe denied making misleading statements, and had said he was axed as part of President Donald Trump's "ongoing war on the F.B.I." and on Mueller.

"I am being singled out and treated this way because of the role I played, the actions I took and the events I witnessed in the aftermath of the firing of James Comey," McCabe has said, referring to Trump's termination of former FBI director Comey last year.

Sessions had testified during his confirmation hearing at the Senate Judiciary Committee in January 2017 that during Trump's presidential campaign he did not have any communications with Russians.

"I have been called a surrogate at a time or two in that campaign and I didn't have — did not have communications with the Russians, and I'm unable to comment on it," Sessions told the committee.

However, it later became known that Sessions had met twice with Russia's ambassador in 2016. One of those meetings occurred two months before the presidential election, but Sessions' spokeswoman said he did not mislead Congress.

ABC News reported Wednesday that McCabe had overseen a criminal investigation of Sessions' statements to Congress, before Mueller, who was appointed special counsel last May, took over that probe as part of his broader inquiry into Russian interference in the 2016 presidential election.

Sessions, who has recused himself from investigations related to Russian meddling, was interviewed in January by Mueller's office.

A source close to Sessions told CNBC that at the time he fired McCabe the attorney general was not aware that he previously had been under the reported criminal investigation.

Sessions' lawyer Chuck Cooper, in an emailed statement to CNBC, said, "The Special Counsel's Office has informed me that after interviewing the Attorney General and conducting additional investigation, the Attorney General is not under investigation for false statements or perjury in his confirmation hearing testimony and related written submissions to Congress."

A spokesman for Mueller declined to comment on Cooper's statement.

The Justice Department directed CNBC to Cooper's statement when asked for comment.

A former high-ranking law enforcement official, when asked about the ABC News report, told CNBC, "This underscores how important it is that the Special Counsel's office be allowed to do what they do and why it can't be handled through the usual course of business at the DOJ."

"This raises questions about the process, timing and role of the Attorney General in the firing" of McCabe, the official said.

"What does it mean to be recused if you can fire everyone involved in the investigation?"

Additional reporting by Eamon Javers