Jeff Sessions first known Cabinet-level official in Trump administration to be interviewed by special counsel.
Attorney General Jeff Sessions was questioned for "several hours" by a special counsel investigation into alleged Russian meddling in the 2016 election, the Justice Department told Anadolu Agency.
The acknowledgement is the first known time that the probe headed by former FBI Director Robert Mueller has interviewed a Cabinet-level official within President Donald Trump's administration.
Justice Department spokesman Ian Prior confirmed the interview with Mueller's office occurred.
Asked if he was worried Sessions was questioned by the special counsel, Trump said: "No, not at all."
Sessions previously recused himself from the ongoing investigation, angering Trump who has reportedly fumed in private meetings with Sessions about the decision. The probe is examining not just Russia's alleged "influence campaign", but whether officials within the Trump campaign conspired with the alleged effort to undercut Democratic nominee Hillary Clinton.
Sessions announced last March that he recused himself from any matter related to the 2016 election, including the Russia probe, amid scrutiny over his failure to disclose to lawmakers during his confirmation he met twice with Russia's former U.S. envoy Sergey I. Kislyak, during the campaign.
The attorney general was a prominent figure in Trump's bid for the White House, and was the first serving senator to endorse then-nominee Trump before heading his campaign's foreign policy team.
His testimony could be vital for Mueller as he examines whether Trump sought to obstruct an FBI investigation into possible collusion between Russia and the Trump campaign by firing former Director James Comey in May.
Comey's abrupt dismissal caught many off guard, including the former director. The FBI is independent from the administration and presidents have rarely taken the extraordinary step of firing a sitting bureau chief. It happened only once before.
Seeking to justify the move, the White House released a Justice Department memo from Deputy Attorney General Rod Rosenstein faulting Comey for his handling of an investigation into Clinton's email server.
The explanation, however, clashed with Trump's stated reason for the move.
During an interview with NBC, Trump said "regardless of recommendation, I was going to fire Comey.
"When I decided to just do it I said to myself, I said, 'you know, this Russia thing with Trump and Russia is a made up story,'" he said.
Rosenstein, the second in command at the Justice Department, appointed Mueller to head the special counsel Russia probe shortly after Comey was dismissed.