Initially it was Rosenstein's memo - critical of Comey's handling of the Hillary Clinton email scandal previous year - that was put forward as the justification for the dismissal.
Senate Democratic Leader Chuck Schumer said Comey should still appear before congressional committees that have invited him to testify.
Days earlier, on May 10, Deputy Press Secretary Sarah Huckabee Sanders told reporters "we don't think it's necessary" to appoint a special prosecutor.
"He knew the day before", the firing, said Sen.
Sen. Claire McCaskill (D-Mo.) said Rosenstein "did acknowledge that he learned Comey would be removed prior to him writing his memo".
The announcement, the latest in the shock-a-day Washington saga, was made by deputy Attorney General Rod Rosenstein.
We have still yet to see any damning evidence that Trump either "colluded" with the Russians or that he obstructed justice in handling the case with recently fired FBI Director James Comey.
The New York Times reported Wednesday that Comey wrote a memo following a dinner meeting with Trump.
How to keep your PC safe from the massive ransomware attacks
NHS organisations across the country are on alert for a possible recurrence of Friday's cyberattack as staff return to work. Microsoft did not confirm to AFP when it made the patch free. "These alerts included a patch to protect their systems".
Thursday's meeting wasn't the first time Trump has privately addressed TV anchors and reporters.
Democrats and Trump's fellow Republicans widely praised Mueller's appointment.
And they wanted the investigations already underway by the Intelligence committees in the House of Representatives and the Senate to keep going, a sentiment Republicans shared.
A number of lawmakers exited the meeting stressing that Mueller's probe, while appropriately diving in to all possible Trump-Russia ties, may make it more hard for current congressional investigations to access vital intelligence.
Mueller's appointment was not expected to affect the FBI or congressional investigations. "We've discussed this before", Spicer said.
"There was no facts laid out as to why you would change that, but appointing a special counsel has created a dynamic for Congress that's going to have to be very leery of crossing into Mr. Mueller's lane".
"My takeaway is everything he said is you have to treat this as if it's a criminal investigation", Graham said.
Rosenstein fielded questions in the closed session for more than an hour, but many senators left the briefing unsatisfied.
Isaiah Thomas Talks To Markelle Fultz About Playing Together With Celtics
The two point guards could be teammates next year, but they're buddies already. "No", Thomas said with a smile. "I talk to him all the time".
"It was a good briefing but there was nothing earth shattering", Sen. Just ask President Bill Clinton; what was originally an inquiry (headed by Ken Starr) into land deals in Arkansas ended up as an indictment of his personal life, causing him all kinds of embarrassment on the world stage and eventually producing a recommendation from the independent counsel that there were sufficient grounds for impeachment.
"We have two very different missions".
"It was a counterintelligence investigation before now".
"I don't think he will sacrifice time for accommodation".
Despite initially opposing appointment of an independent counsel, Republican House Speaker Paul Ryan said Thursday that the development "helps assure people and the Justice Department that they're going to go do their jobs independently and thoroughly, which is what we've called for all along".
And yet, on May 3, Comey himself told the Senate under oath that he had not been politically pressured to halt any investigation.
Republican Sen. Richard Burr of North Carolina, the panel's chairman, said Flynn's lawyer told him that the retired army general, whom President Donald Trump fired in February, would not honor the committee's subpoena to produce documents related to the Russian Federation investigation.
McClatchy says Flynn declined to OK a request from Obama officials to approve a military operation involving the IS stronghold of Raqqa, effectively delaying the operation.
With waiver, US lets Iran keep getting benefits of nuke deal
Analysts have said that his extension of the sanctions is indicative of his tacit intention to let the deal remain. He said the United States will never allow the regime in Iran to acquire a nuclear weapon.
"General Flynn's attorneys have not yet indicated their intentions regarding the Senate Intelligence Committee's subpoena. Consistent with the Committee's position since the beginning of or investigation, I welcome their willingness to cooperate", Burr spokeswoman Rebecca Glover said.
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