House Intelligence Committee Chairman Devin Nunes has set a Tuesday deadline for the Justice Department to provide documents related to an alleged FBI informant looking for suspicious ties to the Russians who spoke with members of President Trump's 2016 campaign.

In a letter sent to Deputy Attorney General Rod Rosenstein on Friday, the California Republican demanded the documents be provided to all committee members "and designated staff," which would go beyond top members of Congress which have been invited to view material related to special counsel Robert Mueller's Russia investigation.

"DOJ continues to obfuscate and delay its production using an array of tactics, such as incorrectly categorizing the requested documents as Gang-of-Eight-level material in order to limit access," Nunes wrote in the letter obtained by the Washington Examiner. "Such conduct by DOJ is unacceptable because the Gang-of-Eight is a legal fiction that has no basis outside of the confines of Presidential approval and reporting of covert actions."

Refusal to comply with the demand to allow lawmakers and "designated staff" to view requested documents would be "an obstruction of a lawful Congressional investigation," Nunes added.

"I will not relent in my duties on behalf of the American public to discover all the facts in this matter," Nunes said at the end of the letter "Any response falling short of this request will be considered an effort to conceal material information from Congress -- a dangerous precedent that threatens the core of our democracy."

The letter was sent after the Justice Department and FBI offered an additional briefing next week to members of the “Gang of Eight,” comprised of congressional leadership from both parties and the top members of the intelligence panels., who were briefed last month on classified intelligence information related to the Russia investigation. By extension, the briefings by top intelligence and law enforcement officials regarded the use of an informant.

While it was initially reported that the briefing was likely to happen Monday or Tuesday, a Justice Department spokesperson confirmed to the Washington Examiner that the briefing is scheduled for Thursday afternoon — after Nunes' deadline — where Rosenstein looks forward to providing "responsive" documents to Nunes and the other members of the Gang of Eight.

"The Deputy Attorney General is representing the United States in a brief unrelated visit to a foreign nation, one of America’s key intelligence partners. He, along with the FBI Director and DNI Coats, look forward to further briefing and again presenting responsive documents to Chairman Nunes and the rest of his colleagues in the Gang of 8 meeting scheduled for Thursday of this week," the spokesperson said.

Last week, a senior DOJ official said that some of the documents to be allowed for review were already made available the classified briefings that were already conducted, "but not inspected by the members at the previous briefing along with some additional material." The Gang of Eight will be allowed to review new documents that were not provided during the original May 24 briefing, the official added.

The briefing was offered to answer certain questions that have been raised by both House Speaker Paul Ryan, R-Wis., and other members.

Reports about an informant sparked sharp rebukes from Trump and his allies, who conjured up the name of "spygate" while alleging that a "spy” — which by definition is different than a confidential source — was improperly sent to scope out his campaign for political purposes.

[Related: Media insist: FBI's source on Trump was an 'informant,' not a 'spy']

Several news outlets have identified the FBI's so-called source as Stefan Halper, a former University of Cambridge professor. In the run-up to last month's briefings, law enforcement officials warned it would not reveal who the source because doing so could put national security and lives at risk.

Democrats said after the briefings last month that they were shown "no evidence" of a spy, but the alarm raised by the Trump campaign was largely abated by top Republicans who were part of the select group of lawmakers that met with DOJ and FBI officials. Notably, Rep. Trey Gowdy, the chairman of the Oversight Committee, who was briefed on the Russia investigation along with the Gang of Eight, cast doubt on there being any wrongdoing on the part of the FBI.

"I am even more convinced that the FBI did exactly what my fellow citizens would want them to do when they got the information they got, and that it has nothing to do with Donald Trump," Gowdy, R-S.C., said in a Fox News interview.

Gowdy was later backed up by Ryan.

However, Nunes distanced himself from Gowdy's assessment. He said last weekend to Fox News that, “What Trey Gowdy’s specifically talking about is this small slice of the investigation that we’re looking at as it relates to whether or not an informant or informants were used."

He added: “You have to remember that Mr. Gowdy loves the FBI and the Department of Justice. If they’re targeting Russians or Chinese or what have you, that’s what we expect them to do. However, the challenge we have in this is that they actually targeted a political campaign that was Donald Trump. And that’s where I think that even though Mr. Gowdy believes that the president’s not a target of this investigation, his campaign is.”

Ryan has also shown support for the DOJ to comply with members' document requests.

"Frankly the sooner the Department of Justice complies with all of our document requests, which are legitimate document requests, the better this is going to be for everybody, and had they complied with the document requests earlier when we made them, we probably could have spared the country of all of this drama," Ryan said Thursday.



Editor's note: This story has been updated with comment from the DOJ.