In an interview with the New York Times, the president also criticized Sessions' recent testimony before a Senate panel which is investigating possible collusion between Moscow and the Trump campaign, saying he had given "some bad answers."
Sessions recused himself from overseeing the Russian probe in March after the Washington Post reported that he met twice with Russian Ambassador Sergey Kislyak during the campaign.
But Trump said Sessions had acted unfairly in taking the job in the first place if he had felt in any way compromised.
"How do you take a job and then recuse yourself? If he would have recused himself before the job, I would have said, 'Thanks, Jeff, but I'm not going to take you,'" Trump said.
"It's extremely unfair -- and that's a mild word -- to the president."
He also engaged in testy exchanges with several senators who pressed him for details on his discussions with Trump -- which he refused to provide in the name of confidentiality.
"Jeff Sessions gave some bad answers," the president said in his interview with the Times.
"He gave some answers that were simple questions and should have been simple answers, but they weren't."
(This story has not been edited by NDTV staff and is auto-generated from a syndicated feed.)
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