After a federal court ruling on Friday restored the White House press pass of CNN's Jim Acosta, the West Wing moved almost immediately to once again contest his access, sources involved in the negotiations tell me.

What's happening: The White House sent CNN a letter Friday giving a chance for Acosta to make the case for continued access. A White House official said a decision will be made after hearing the case.

CNN is fighting back, and is expected back in court as soon as today.

Acosta was blocked after clashes with President Trump, who accused the reporter of hogging the microphone at a post-midterm press conference.

after clashes with President Trump, who accused the reporter of hogging the microphone at a post-midterm press conference. A CNN spokesperson told me: "The White House is continuing to violate the First and Fifth amendments of the Constitution. These actions threaten all journalists and news organizations. Jim Acosta and CNN will continue to report the news about the White House and the President."

"The White House is continuing to violate the First and Fifth amendments of the Constitution. These actions threaten all journalists and news organizations. Jim Acosta and CNN will continue to report the news about the White House and the President." White House press secretary Sarah Sanders, speaking on Fox News, accused the correspondent of "grandstanding": "[I]f certain reporters like Jim Acosta can't be adults, then CNN needs to send somebody in there who can be."

Why it matters: This is a high-risk confrontation for both sides. It turns out that press access to the White House is grounded very much in tradition rather than in plain-letter law.

So a court fight could result in a precedent that curtails freedom to cover the most powerful official in the world from the literal front row.

How CNN sees the fight ... Brian Stelter, CNN's chief media correspondent, wrote in his Reliable Sources newsletter last night:

"From the looks of the letter, the W.H. is trying to establish a paper trail that will empower the administration to boot Acosta again at the end of the month."

How the White House sees the fight ... Sanders said Friday in an interview with her father, former Arkansas Gov. Mike Huckabee, filling in for Sean Hannity: "We've laid out in a letter to CNN and their team what we think were some of the missteps that their reporter made at the press conference on November 7th."

"[T]he judge, I think, was actually very clear that the White House has the ability to say: You can't come in . You don't have — freedom of the press doesn't mean freedom into the White House. And he said there has to be due process. And so that's what we're doing and we'll see what happens from there."

I think, was actually very clear that . You don't have — freedom of the press doesn't mean freedom into the White House. And he said there has to be due process. And so that's what we're doing and we'll see what happens from there." Sanders added that CNN has "50-plus" journalists who hold passes: "So the idea that they aren't able to get information that they need from the White House is frankly laughable."

"[T]radition has been in the past that the White House Correspondents' Association determines who sits in [the press] room and who sits in those individual seats," Sanders continued.

Mike Huckabee interjected: "But that's tradition. It's not law."

"But that's tradition. It's not law." Sanders responded: "True."

"True." Asked about bringing in reporters from elsewhere in America, Sanders said: "I think that's certainly an option to explore."

Trump, asked about the Acosta ruling by Chris Wallace on "Fox News Sunday," said: "If he misbehaves, we’ll throw him out or we’ll stop the news conference."

"I think one of the things we’ll do is maybe turn the camera off that faces them [the reporters] because then they don’t have any airtime. Although I’ll probably be sued for that and maybe, you know, win or lose it — who knows."

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