Lewandowski did not say if he has been contacted by Trump or anyone on his staff about returning. Trump will also take more questions directly from the media.
Dubke's job was to work behind-the-scenes managing the White House communications strategy and responses to crises, such as the firing of FBI director James B. Comey, the investigation into Russian interference with the 2016 US election, and Jared Kushner's allegedly back channel communications with the Kremlin.
Melania Trump says it was "simply wrong" for celebrity Kathy Griffin to appear in a video holding what looked like President Donald Trump's bloody, severed head.
However, Trump has privately and publicly pinned much of the blame for his administration's woes on the communications effort.
Multiple reporters confirmed the latest creative initiative to avoid addressing one of the most pressing and concerning national security questions in recent history. "In terms of achievement, I think I'd give myself an A. Because I think I've done great things, but I don't think I have - I and my people, I don't think we've explained it well enough to the American public". Sean Spicer and Trump himself just keep screaming about fake news, but Spicer wouldn't deny that the story is true and others have been out there saying he was right to do it.
"I think Mike is a very capable guy", Mr. Lewandowksi said. "He's always proven that".More news: Upton Not Happy With Trump Climate Decision
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"It is my opinion that numerous leaks coming out of the White House are fabricated lies made up by the #FakeNews media", Trump tweeted.
The Comey associate, who wasn't authorised to discuss details of the testimony and spoke on condition of anonymity, declined to discuss the content of Comey's planned testimony.
Aside from Kasowitz, the White House is considering bringing on old campaign hands to help manage the fallout.
A Republican consultant, Dubke joined the White House team in February after campaign aide Jason Miller " Trump's original choice for communications director " withdrew from consideration.
The CNN report notes that Spicer "is also frustrated by the media's treatment of him", notably reports that he "chafes at reports suggesting Trump is planning to shake up the communications team because he isn't satisfied with Spicer's performance".
First and foremost, President Donald Trump changes his views frequently, and sometimes dramatically, said Hagle.