Denouncing the creation of a special counsel to investigate his campaign's ties with Russia, Mr Trump said on Thursday that the move "shows we're a divided, mixed-up, not unified country" and is "a very, very negative thing".
Pressed for the first time by White House reporters on why he fired Comey, the President rejected reports that he had leaned on the FBI Director during a White House meeting to drop a probe of former National Security Adviser Michael Flynn.
No, said Democrats, suggesting that special counsel Robert Mueller may not be a truly independent investigator because he will answer to the Justice Department and Attorney General Jeff Sessions.
Meanwhile, Republican Senator Lindsey Graham says this appears to be going in the way of a criminal investigation - which could limit the ability of Congress to look into this. "That gives me confidence and should give the American people some confidence". He is required to tell Congress when the probe concludes, but publicly revealing anything beyond that is up to Rosenstein's discretion. And Geoff, senators weren't shy about coming to the microphones after they heard from the deputy attorney general.
In the Senate meeting, Rosenstein told the senators that, in fact, Trump had made a decision to fire Comey the day before he wrote his memo.
Mueller will have almost unfettered access to witnesses and information, and the ability to bring criminal charges.
Trump's own timeline and rationale for firing Comey has repeatedly been amended by his administration.
A combination photo shows (from left) US President Donald Trump, White House National Security Advisor Michael Flynn and Federal Bureau of Investigation director James Comey.
Illinois Democrat Dick Durbin echoed McCaskill, saying Rosenstein told lawmakers that he knew of Trump's intent the day before he wrote a document that the White House initially said was the main reason Comey was dismissed. He has served presidents of both political parties and, after taking the director job days before the September 11 attacks, oversaw the FBI's terrorism-fighting efforts over the next decade.
Responding to US President Donald Trump's claim that he is a victim of the "witch hunt", Florida Senator Macro Rubio said that the former is entitled to his opinion, but the United States is a "nation of laws". The President's anger contrasted with a more measured written statement released by the White House on Wednesday evening, when Mr Trump declared that a thorough investigation would find "no collusion between my campaign and any foreign entity".
Earlier, Mr Trump had taken to twitter to vent his frustration at the appointment of former FBI director Robert Mueller to oversee an investigation into Russian Federation.
The overall consensus among Senate members is that the Russian Federation investigation is getting more serious. "Russia is fine." On whether the questions surrounding Russian Federation and his campaign were divisive, Trump added: "I think it divides the country".