Senior Justice Department and FBI officials have a collective anti-Republican bias and have “politicized the sacred investigative process,” President Donald Trump tweeted Friday.

The broadside came just hours before he is expected to clear House Republicans to release a controversial memo charging the bureau with overstepping its authority.

White House officials say the president “is OK” with the contents of a document compiled by House Intelligence Chairman Devin Nunes that alleges the FBI abused its power in obtaining a Foreign Intelligence Surveillance Act warrant on a former Trump campaign adviser. He will clear Nunes to make it public over “grave” FBI, Justice and intelligence community objections later Friday — and he started the day going after the leadership of those agencies.

Trump tweeted that the “top Leadership and Investigators” at Justice and the FBI “have politicized the sacred investigative process in favor of Democrats and against Republicans,” an allegation he wrote would once have been “unthinkable.”

The president appeared to be lashing out at, among others, Jeff Sessions and Christopher Wray, his hand-picked attorney general and FBI director. While Justice and FBI officials have typically operated with ample independence from the White House, Trump reportedly has asked many law enforcement officials if they are on his “team.”

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Democrats and former officials warn he is trying to force out Deputy Attorney General Rod Rosenstein, who is overseeing the Russian probe, so he can appoint a new deputy who will fire the special counsel and close the probe.

Democratic members and some former national security officials have said Republicans’ real aim in releasing the memo is to undermine the Justice Department’s Russia election meddling probe being led by special counsel Robert S. Mueller III. Trump’s Friday morning Twitter attack on the department will only further fuel such allegations.

The top Leadership and Investigators of the FBI and the Justice Department have politicized the sacred investigative process in favor of Democrats and against Republicans – something which would have been unthinkable just a short time ago. Rank & File are great people!

— Donald J. Trump (@realDonaldTrump) February 2, 2018

The president’s tweet — and one that followed — appeared to come during his morning habit of watching the “Fox & Friends” program on the Fox News Channel. He quoted Judicial Watch’s Tom Fitton, who was on the program around 7 a.m., criticizing 2016 Democratic presidential nominee Hillary Clinton for her campaign’s involvement in paying for a dossier of unflattering information about Trump and Russia that was compiled by a freelance investigator — and a former British spy — for Fusion GPS, a research firm.

“You had Hillary Clinton and the Democratic Party try to hide the fact that they gave money to GPS Fusion to create a Dossier which was used by their allies in the Obama Administration to convince a Court misleadingly, by all accounts, to spy on the Trump Team.” Tom Fitton, JW

— Donald J. Trump (@realDonaldTrump) February 2, 2018

Appearing on @FoxFriendsFirst next hour to discuss #ReleaseTheMemo. It looks like today is the day for some accountability for the Deep State… @JudicialWatch @FoxNews @realDonaldTrump. pic.twitter.com/lPAPgd2hk8

— Tom Fitton (@TomFitton) February 2, 2018

Friday marks the end of a five-day presidential review period started by a party-line panel vote to release the document. The FBI director and senior congressional Democrats oppose the memo being made public, arguing it could undermine national security and that it cherry-picks information without context or other facts.

The official told reporters traveling Thursday with the president that White House officials have been studying the Nunes-crafted memo to make sure “it doesn’t give away too much in terms of classification.”

“The president is OK with it,” the White House official said. “I doubt there will be any redactions. It’s in Congress’ hands after that.”

In an example of how many House Republicans have rushed to endorse releasing the Nunes memo and defend Trump, Rep. Jeff Duncan tweeted Thursday that he has read it and believes it will “shake the organization (FBI) to its core.” The document will show “Americans just how the agency was weaponized by the Obama officials/DNC/HRC to target political adversaries,” the South Carolina Republican wrote.

Having read “The Memo,” the FBI is right to have “grave concerns” – as it will shake the organization down to its core – showing Americans just how the agency was weaponized by the Obama officials/DNC/HRC to target political adversaries. #ReleaseTheMemo

— Rep. Jeff Duncan (@RepJeffDuncan) February 1, 2018

House Intelligence ranking member Adam Schiff on Wednesday night alleged that the committee’s Nunes-led majority made “material changes” to the version the panel voted, along party lines, to make public before it was handed over to the White House.

That led House Minority Leader Nancy Pelosi and Senate Minority Leader Charles E. Schumer both to say Thursday that Nunes’ alleged changes to the version the committee voted on disqualify him from continuing in the post. They asked Speaker Paul D. Ryan to remove Nunes; Ryan responded by defending the chairman and saying the document should be released.