The Department of Justice is declining to give top conservatives in Congress a memo Deputy Attorney General Rod Rosenstein sent to special counsel Robert Mueller in August authorizing and outlining the scope of the Russia investigation, citing the ongoing nature of the investigation.

In an April 30th letter obtained by CBS News' Andres Triay, Assistant Attorney General Stephen Boyd tells Rep. Mark Meadows, R-North Carolina, and Jim Jordan, R-Ohio, the DOJ will not be providing the so-called "scope" memo. Meadows, the chairman of the conservative House Freedom Caucus, and Jordan had requested the memo in an April 9 letter. Rosenstein appointed Mueller to the post of special counsel in May 2017, after President Trump fired former FBI Director James Comey.

"On May 17, 2017, the deputy attorney general appointed the special counsel and issued a one-page appointment order," Boyd wrote. "Consistent with longstanding Department of Justice policy, the appointment order did not identify specific investigations involving specific individuals. In the confidential August 2 memorandum, the deputy attorney general described allegations that fell within the scope of the special counsel's investigation. As you know, that investigation is ongoing."

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"The filed memorandum contained redactions to avoid disclosing internal communications between the special counsel and deputy attorney general about active criminal investigations, to protect classified information, and to comply with the longstanding general policy of the department against confirming or denying information about active investigations," Boyd continued. "The department recognizes the keen interest that Congress has in the special counsel's investigation, but respectfully, we must adhere to the longstanding position of the department that congressional inquiries pertaining to ongoing criminal investigations threaten the integrity of those investigations."

Mr. Trump has expressed frustration recently over what he views as DOJ's failure to turn over documents to Congress, most recently criticizing the "rigged system" in a rather tweet Wednesday morning.

"A Rigged System — They don't want to turn over Documents to Congress. What are they afraid of? Why so much redacting? Why such unequal 'justice?'" Mr. Trump tweeted. "At some point I will have no choice but to use the powers granted to the Presidency and get involved!"

A Rigged System - They don’t want to turn over Documents to Congress. What are they afraid of? Why so much redacting? Why such unequal “justice?” At some point I will have no choice but to use the powers granted to the Presidency and get involved! — Donald J. Trump (@realDonaldTrump) May 2, 2018

In an interview on "Fox and Friends" last week, Mr. Trump said he has avoided getting involved in the Justice Department so far, but that might not last.

"They have a witch hunt against the president of going on," the president said on the morning show. "I have taken the position, and I don't have to take this position and maybe I'll change, that I will not be involved with the Justice Department. I will wait until this is over. It is a total – it is all lies and it is a horrible thing that is going on, a horrible thing."