The Justice Department watchdog's investigation into Foreign Intelligence Surveillance Act abuse might not be winding down yet.

Former top FBI lawyer James Baker said this week he is cooperating with the Justice Department inspector general's investigation.

"I have had a longstanding relationship with the inspector general's office, because I firmly believe in the appropriateness and the need for effective oversight of the FBI," Baker said in a CNN interview.

Baker's admission is another sign that despite what Attorney General William Barr said earlier this year, Inspector General Michael Horowitz's investigation may not be completed by early June.

A focus of Horowitz's investigation is the FBI's use of an unverified dossier on President Trump's ties to Russia, written by British ex-spy Christopher Steele, to obtain warrants to surveil onetime Trump campaign official Carter Page.

Although Fox News host Sean Hannity said this week that sources were telling him Barr may already have a copy of the inspector general's report on the FISA abuse investigation, a British newspaper reported Horowitz may soon be interviewing Steele, casting into further uncertainty the status of the inquiry.

Baker took a lead role in reviewing those FISA applications before submitting them to the FISA court. He has said he took the information "seriously" but "not necessarily literally," and also that he is "nervous" about Horowitz.

Baker told CNN he is also open to helping Attorney General William Barr and U.S. Attorney John Durham with their review of the origins of the Russia investigation. He stressed that it was a "small group" who led the FBI's counterintelligence inquiry into Trump's campaign, namely former FBI Director James Comey and former Deputy Director Andrew McCabe.

Baker was appointed FBI general counsel in January 2014 and reassigned by FBI Director Christopher Wray in December 2017. Last year, it was reported that Baker was resigning, and since has written for the Lawfare blog and joined the conservative think tank R Street Institute.

He is also under criminal investigation for alleged unauthorized leaks to the media during his time at the bureau.