WATCH: Jeff Sessions forced to resign from US attorney general post

WATCH: Jeff Sessions forced to resign from US attorney general post

Transcript for Jeff Sessions forced to resign from US attorney general post

And it did not take long. Just hours after the results of the midterm elections and that split victory for president trump, today, the president demanded his attorney general, Jeff sessions, resign. Sessions submitting this letter, beginning by writing, “At your request, I am submitting my resignation.” And these images just a short time ago. Jeff sessions leaving the justice department for the last time. Growing emotional. This has been a very turbulent relationship between the A.G. And the president. The president furious from the start that sessions recused himself in the Russia investigation. Tonight, the president’s move shifts the focus immediately from the midterms to the Mueller investigation. Is it in danger? ABC’s Jonathan Karl tonight on the phone call to sessions and the message from the president. Reporter: This morning, just before president trump’s post-election news conference, chief of staff John Kelly called attorney general Jeff sessions with a message from the president — resign today. Sessions has been on thin ice for nearly two years. One of trump’s earliest and staunchest supporters, he infuriated the president shortly after becoming A.G. By recusing himself from the Russia investigation. I am disappointed in the attorney general. He should not have recused himself. Reporter: The attorney general’s decision ultimately led to the appointment of special counsel Robert Mueller. Trump never forgave him. If he was going to recuse himself, he should have told me before he took the job and I would have picked somebody else. Reporter: For months, the president publicly humiliated the attorney general. Well, it’s kind of hurtful, but the president of the united States is a strong leader. Reporter: Tonight, sessions applauded as he walked out of the justice department building for the last time. The president quickly named sessions’ chief of staff, Matt Whitaker, as the acting attorney general, tweeting, “He will serve our country well.” Whitaker is now the ultimate authority over the special counsel investigation. In the past, president trump has suggested he wants an attorney general who will protect him. And in Whitaker, he has picked someone who has talked openly about reining in Robert Mueller. Last year, when the president said Mueller would be crossing a red line if he investigated the trump family business and finances, Whitaker, then a CNN contributor, wrote, “The president is absolutely correct. That goes beyond the scope of the appointment of the special counsel.” And in a television appearance, Whitaker defended the infamous trump tower meeting. Donald Trump Jr., Paul manafort and Jared Kushner sitting down with a Russian lawyer they were told had dirt on Hillary Clinton. You would always have somebody from the campaign take the meeting and hear that person out. Reporter: Whitaker also openly about how an acting attorney general could effectively put an end to the Russia investigation. I could see a scenario where Jeff sessions is replaced with a recess appointment and that attorney general doesn’t fire Bob Mueller, but he just reduces his budget to so low that his investigation grinds to a halt. And Jon Karl with us live tonight from the white house. Jon and I on the air until the wee hours of the morning covering the midterm. Jon, you’re back at it at the white house. Democrats are already calling on the new attorney general Matthew Whitaker to recuse himself from the Russia investigation. Even some Republicans sounding concerned? Reporter: Democrats are warning of a constitutional crisis, if Whitaker doesn’t recuse himself and interferes in any way with the investigation. And some Republicans are expressing concerns, as well, including Susan Collins and senator-elect Mitt Romney, who today warned, saying that it was imperative that the investigation proceeds to its conclusion unimpaled. David? Jon Karl, thank you. Another major question about this tonight, does this president pressure on Robert Mueller to wrap this up, to issue his findings. With Democrats and some Republicans concerned about whether this investigation will be proexticketed. Let’s get to Pierre Thomas tonight. How soon could we see Mueller’s report? Reporter: Yes, this does create pressure for Mueller to complete the job. Whitaker has said that if Mueller investigates the president’s finances, the investigation could look like a mere whit hunt. That said, Mueller’s not someone to buckle to pressure. He’ll end this investigation when he sees fit. Some of my sources are hoping Mueller will wrap up by the end of the year, with more indictments potentially coming sooner, possibly in weeks or days. David? Pierre Thomas, thank you. As we said, Jeff sessions’

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