White House press secretary Sean Spicer abruptly resigned Friday in protest at a major shake-up of Donald Trump's scandal-tainted administration, as pressure mounted from a broadening investigation into the Trump campaign's ties to Russia.
Spicer quit after Trump named Anthony Scaramucci, a Wall Street financier and one-time critic, as the new White House communications director -- a role Spicer had hoped to play.
"It's been an honor & a privilege to serve @POTUS @realDonaldTrump & this amazing country. I will continue my service through August," Spicer tweeted.
In a written statement, Trump said he was "grateful" for Spicer's work and praised his "great television ratings" -- a reference to Spicer's keenly watched, combative and often-satirized news briefings.
"Spicer is a wonderful person who took tremendous abuse from the Fake News Media - but his future is bright!" Trump tweeted.
Spicer was replaced by deputy press secretary Sarah Huckabee Sanders.
In an interview with Fox News, Spicer said he stepped aside to "not have too many cooks in the kitchen" to convey Trump's message.
Trump used the occasion of Spicer's departure to lash out at the media, claiming his administration had "accomplished so much" and been "given credit for so little."
"The good news is the people get it even if the media doesn't," Trump added.
Spicer's resignation marked an escalation of tensions within an administration that has seen its legislative agenda falter at the same time it has been buffeted by an investigation into alleged collusion with Russia.
The Washington Post reported late Friday that Attorney General Jeff Sessions, contrary to his prior testimony, discussed campaign-related and policy matters with Russia's ambassador to Washington, citing intelligence intercepts.
The report will heap pressure on Sessions, who already was on the receiving end of a tongue-lashing by Trump over the Russia probe. The president suggested Sessions had betrayed him in stepping away from the investigation.
And in another blow, Mark Corallo -- who was coordinating the Trump legal team's public response to the Russia crisis -- told AFP that he, too, had stepped down.
After months of denials, the White House was recently rocked by emails showing Donald Trump's eldest son and two top aides met with a Russian lawyer in the belief they would get dirt on the Republican billionaire's 2016 election rival, Hillary Clinton.
In response, Trump aides have floated the idea of pre-emptive presidential pardons and Trump himself has warned investigators not to look into his family finances.
Spicer's decision appears to have happened quickly, with neither he nor Sanders giving any indication of changes afoot when they had drinks with a group of journalists on Thursday evening.
Spicer had "no regrets" on his way out the door, he said on Fox late Friday.
Yet he angrily lashed out at US media, claiming they were "obsessed" with Russia after US intelligence agencies said that Moscow was involved in meddling with the US presidential election Trump won.
"I was increasingly disappointed in how so many members of the members here in the media do their job, or rather, don't do their job. The bias which they come from it at," Spicer said.
And it is no exception, he stressed.
"The majority of folks that are now in this -- in the briefing room, that are going into journalism. They're not there for the facts and the pursuit of the truth. Rather, they're trying to figure out, how do I get on TV, how do I become a YouTube star. And that's disappointing."
- 'On track' -
Scaramucci struck a collegial tone as he took questions from the press for the first time.
He dismissed reports of infighting, telling reporters: "I think the White House is on track."
"I've seen this guy throw a dead spiral through a tire. I've seen him at Madison Square Garden with a topcoat on, standing in the key and hitting foul shots and swishing them. He sinks three-foot putts. I don't see this as a guy who's ever under siege."
Spicer had been a close ally of chief of staff Reince Priebus, and his departure will likely weaken both Priebus and the bridge between the White House and the Republican Party establishment.
- Legal shake up -
In an expansive interview with The New York Times earlier this week, Trump plunged his White House into fresh crisis when he attacked special counsel Robert Mueller, and warned him against looking at Trump family finances.
Mueller is examining whether Trump or his aides colluded with Russia's apparent efforts to help tilt the 2016 presidential election in Trump's favor.
With the probe apparently extending to financial transactions, US media reported that Trump allies were looking for ways to discredit Mueller's investigation.
Trump himself has suggested that Mueller — a widely respected former FBI director — may have a conflict of interest.
The White House has pointedly refused to rule out the possibility that Trump would fire Mueller -- an act that would prompt a political firestorm and perhaps a constitutional crisis.
Republican House Homeland Security Committee chairman Michael McCaul warned Trump would face a "tremendous backlash response from both Democrats but also House Republicans" if he were to sack Mueller.
"Trump cannot define or constrain Mueller investigation. If he tries to do so this creates issues of constitutional and criminal dimension," said former attorney general Eric Holder.
Trump has already fired his FBI director James Comey over the Russia investigation.
The top Democrat on the Senate's intelligence committee, Mark Warner, warned that pardoning anybody who may have been involved in potential collusion "would be crossing a fundamental line."