Whitaker is poised to take over the Russian Federation investigation, a probe he has criticized in the past.
The Democrats, who won the House in the mid-terms, have vowed to protect it. "Special Counsel Mueller must be allowed to complete his work without interference-regardless of who is AG". Senator Susan Collins and Mitt Romney said it should not be impeded in any way.
Sessions' decision to recuse himself in March 2017 was based on his involvement with the Trump campaign during the 2016 presidential election. Mueller's team also has been pressing for an interview with Trump.
Democrats see this latest move as an attempt to do just that.
Whitaker, a former USA attorney for the Southern District of Iowa, had served as Sessions's chief of staff since September 2017. Schumer and Democrat Nancy Pelosi, who is likely to become House speaker next year, called on Whitaker to recuse himself, with Schumer citing "his previous comments advocating defunding and imposing limitations on the Mueller investigation". However, the publication cited anonymous sources, and added that it was not clear how serious the president was about the idea.More news: Big retailers gear up for Black Friday
NPR: "Jeff Sessions Forced Out As Attorney General After Constant Criticism From Trump" - "Jeff Sessions, the president's earliest and most fervent supporter in Congress, stepped down as attorney general Wednesday after brutal criticism from the president, bringing an abrupt end to his controversial tenure as the nation's top law enforcement officer".
Mr Trump has at various times belittled Mr Sessions as "beleaguered", "VERY weak", and "DISGRACEFUL".
Trump had repeatedly criticized Sessions for recusing himself from any investigation into potential Russian meddling in the 2016 US presidential election.
"Sessions noted in his resignation letter to the president that he was stepping down 'at your request'".
That left Rosenstein overseeing the investigation, and he named Mueller as special counsel.More news: Brad Pitt ‘concerned’ about his upcoming custody trial
Trump has said for months that he wished to replace Sessions, but lawmakers and administration officials believed that firing the attorney-general before the midterm elections would have had negative consequences for Republicans in tight races.
A Kremlin spokesman, Dmitry Peskov, on Thursday called Mueller's investigation a "headache" for USA authorities but said it "has nothing to do with us", and he declined to comment on Sessions' departure.
Sessions had recused himself from Mueller's investigation, leaving oversight to Deputy Attorney General Rod Rosenstein.
Mr Mueller could seek to challenge his own firing if he felt Whitaker lacked the good cause required by the special counsel regulation, said Mr Ohlin.More news: Tamera Mowry-Housley Searches For Niece Missing In Thousand Oaks Shooting