Whitaker, who is at least temporarily replacing Sessions, said in a 2017 CNN interview that "I could see a scenario where Jeff Sessions is replaced, it would recess appointment and that attorney general doesn't fire Bob Mueller but he just reduces his budget to so low that his investigations grinds to nearly a halt".
Trump repeatedly has said over the previous year that he regretted making Sessions attorney general.
Sessions had faced pressure from Trump and other Republicans for his recusal from the investigation headed by special counsel Robert Mueller, who is looking into alleged Russian election interference during the 2016 election.
"We thank Attorney General Jeff Sessions for his service, and wish him well!" the president continued.
Were he nominated, this wouldn't be Kobach first time in the Trump Administration.
Keep checking the WSAZ App and WSAZ.com for the latest information. Whitaker said in a May 2017 statement: "I believed there was a strong case to bring against [Clinton] and she should be extremely grateful that has not happened". It does not take a lawyer or even a former federal prosecutor like myself to conclude that investigating Donald Trump's finances or his family's finances falls completely outside of the realm of his 2016 campaign and allegations that the campaign coordinated with the Russian government or anyone else.More news: Ariana Grande performs 'Thank U, Next' in a wedding dress
Sessions' abrupt departure from the Justice Department is nearly certainly related to the Democrats' victory in the House of Representatives, and its implications in the Special Counsel investigation.
Donald Trump with Mr Sessions in December past year.
Last year, Whitaker wrote an op-ed for CNN that accused Mueller's investigation of going too far.
During a press conference at the White House Wednesday, President Trump said he is satisfied with the performance of "most of his Cabinet", but left room for major changes in the coming days and weeks.
"Most importantly as my time as attorney general, we have restored and upheld the rule of law".
Sessions said that he did not think he should lead the investigation since he had been a Trump campaign surrogate.
Mr Sessions was widely expected to step down in the wake of the United States midterm elections, which saw the Republican party retain their majority in the Senate, but lose control of the House of Representatives.