The new acting attorney general or whoever serves as his fulltime replacement could simply brief Trump and his aides on where the special counsel is focused if the president doesn't know already. Though Sessions was an early and prominent campaign backer of Trump, his departure letter lacked effusive praise for the president and made clear the resignation came "at your request".
But it's not typical for chiefs of staff to replace the head of an agency when that head resigns, as former CIA staffer and NBC contributor Ned Price pointed out.
Mr Trump also tweeted an attack on the Robert Mueller's probe into the Russian collusion, quoting an NBC News survey on public perception of the probe. "That's why Cabinet Secretaries have Deputies". Trump, who denies any collusion, has long complained about the probe, calling it a witch-hunt.
About six Congressional Democrats including Senators Bernie Sanders, Elizabeth Warren, Ron Wyden and Cory Booker stressed that Trump may be attempting to disrupt the Mueller investigation and called on Whitaker to recuse himself.
Whitaker so far hasn't said much about his outlook for the Justice Department or the special counsel investigation; Rosenstein hasn't spoken publicly either since Sessions' dismissal.
He was the co-chairman of former Texas Gov. Rick Perry's 2012 Iowa campaign for president, and campaigned himself for the Senate seat opened by the retirement of Democrat Tom Harkin.
Some Democrats also considered Sessions too eager to do Trump's bidding and overly receptive to his grievances. The recusal left the investigation in the hands of Rosenstein, who appointed Mueller as special counsel two months later after Trump fired then-FBI Director James Comey. "By forcing the firing (of) the attorney general, the president now threatens the rule of law itself".More news: Early voting period ending in MA
Asked whether Whitaker would assume control over Mueller's investigation, Justice Department spokeswoman Sarah Flores said Whitaker would be "in charge of all matters under the purview of the Department of Justice". Trump said Wednesday that he did not plan to stop the investigation.
He found satisfaction in being able to reverse Obama-era policies that conservatives say flouted the will of Congress, encouraging prosecutors to pursue the most serious charges they could and promoting more aggressive enforcement of federal marijuana law.
FILE PHOTO: U.S. President Donald Trump and Attorney General Jeff Sessions stand for the national anthem at a graduation ceremony at the FBI Academy on the grounds of Marine Corps Base Quantico in Quantico, Virginia, U.S. December 15, 2017. Chuck Schumer, said he should recuse himself because of his comments on the probe. Rep.
The Democrats, who won the House in the mid-terms, have vowed to protect it.
A copy of Attorney General Jeff Sessions' resignation letter is photographed in Washington on an image of the exterior of the Justice Department. Trump's advisers are privately expressing worries that the special counsel, who's been out of the news for the past month, has been stealthily compiling information and could soon issue new indictments or a damning final report.
The American Civil Liberties Union (ACLU) Executive Director Anthony Romero said in a statement on Wednesday that the US Senate must ensure that whomever Trump nominates to replace Sessions will not interfere in Mueller's Russian Federation investigation.
A permanent replacement for Sessions must be confirmed by the Senate, which Trump's Republicans will continue to control as a result of Tuesday's midterm elections.