Brennan played a ‘prominent role’ in Russia probe.

He briefed Harry Reid about Trump associates’ contacts with Russians.

Reid believed that Brennan had an ‘ulterior motive.’

A book published in March offered a startling but little-noticed revelation about former CIA Director John Brennan. According to “Russian Roulette,” Senate Minority Leader Harry Reid believed Brennan was using him as a conduit to publicize possible links between Trump campaign associates and the Russian government.

Brennan’s contacts with Reid — and other activities during the 2016 presidential campaign — are of “significant” interest to congressional investigators trying to figure out the ex-spy’s early role in the Russia investigation, The Daily Caller News Foundation is told.

“By his own account, Brennan played a prominent role in starting the investigation of Trump’s team,” a congressional source with direct knowledge of the House of Representatives’ Russia investigations tells TheDCNF.

“Investigators in Congress suspect there are important details about his role that he hasn’t revealed, and we’re trying to get to the bottom of it.”

According to “Russian Roulette,” by Yahoo! News chief investigative correspondent Michael Isikoff and David Corn, the Washington bureau chief of the left-wing Mother Jones magazine, Brennan contacted Reid on Aug. 25, 2016, to brief him on the state of Russia’s interference in the presidential campaign. Brennan briefed other members of the so-called Gang of Eight, but Reid is the only who took direct action.

Two days after the briefing, Reid wrote a letter to then-FBI Director James Comey asserting that “evidence of a direct connection between the Russian government and Donald Trump’s presidential campaign continues to mount.” (RELATED: Book Reveals That Christopher Steele Is ‘Fifty-Fifty’ On ‘Golden Showers’ Tape)

Reid called on Comey to investigate the links “thoroughly and in a timely fashion.”

Reid saw Brennan’s outreach as “a sign of urgency,” Isikoff and Corn wrote in the book.

“Reid also had the impression that Brennan had an ulterior motive. He concluded the CIA chief believed the public needed to know about the Russian operation, including the information about the possible links to the Trump campaign.”

According to the book, Brennan told Reid that the intelligence community had determined that the Russian government was behind the hack and leak of Democratic emails and that Russian President Vladimir Putin was behind it. Brennan also told Reid that there was evidence that Russian operatives were attempting to tamper with election results.

Reid’s letter referred to some public reporting about Trump campaign associates’ links to the Kremlin, but he also included a reference to information that may not have been made public at the time. He cited allegations that were included in the infamous Steele dossier about Carter Page, an adviser to the Trump campaign at the time.

Reid wrote of a “series of disturbing reports” about a trip that Page had made to Moscow in July 2016.

It is still not clear who provided Reid with the information about Page.

It is not known whether Brennan would have passed the information to Reid. Isikoff and Corn report that Glenn Simpson, the founder of the opposition research firm that commissioned the dossier, had not briefed Reid.

Marc Elias, a lawyer for the Clinton campaign, DNC, and Reid’s super PAC, knew of the allegations against Page. Elias, who hired Simpson’s firm, Fusion GPS, had also relayed the information to Robby Mook, the Clinton campaign manager, Isikoff and Corn reported.

“However Reid learned about the Page allegation, his reference to a meeting with ‘sanctioned individuals’ was significant. Though no reporters picked up on that sentence, it was the first time Steele’s unconfirmed reporting had seeped into the public discourse,” the authors wrote.

Congressional investigators are interested in finding out if Brennan, who is now an MSNBC analyst, pressured Congress or the FBI to reveal details of the Russia investigation. The House Permanent Select Committee on Intelligence recently sent Brennan and other top Obama administration officials letters with a list of questions about their actions during the Russia probe. Brennan provided a response to those questions last month.

Despite his formative role in the investigation, Brennan has acknowledged that he was unsure at the time whether collusion between the Trump campaign and Russian government actually occurred.

“I don’t know whether such collusion existed. I don’t know,” Brennan testified before the House Permanent Select Committee on Intelligence on May 23, 2017.

“I don’t have sufficient information to make a determination whether or not such cooperation or complicity or collusion was taking place, but I know there was a basis to have individuals pull those threads,” he said at another point during his testimony.

Brennan claimed that though he did not have conclusive evidence of collusion, he believed “there was a sufficient basis of information and intelligence that required further investigation by the bureau to determine whether or not U.S. persons were actively conspiring and colluding with Russian officials.”

“I was concerned about because of known Russian efforts to suborn” members of the Trump campaign, he added.

Brennan did not identify who he believed may have been suborned, but it is now believed that he was referring to Carter Page and George Papadopoulos, another former Trump campaign aide.

Papadopoulos was reportedly the impetus of the collision investigation. In April 2016, he met in London with a professor named Joseph Mifsud. Mifsud told Papadopoulos that the Russian government had obtained “thousands” of Clinton-related emails.

The next month, Papadopoulos met in a bar with Alexander Downer, the Australian High Commissioner to the United Kingdom. Downer allegedly claims that Papadopoulos told him about hacked Clinton emails. Two months later, that information was passed to the FBI. The investigation into possible campaign collusion was opened on July 31, 2016. (RELATED: EXCLUSIVE: A London Meeting Before The Election Aroused George Papadopoulos’s Suspicions)

In a Feb. 4 interview on “Meet the Press,” Brennan was asked how U.S. intelligence obtained information about Papadopoulos.

Brennan responded that he was not “going to get into details about how it was acquired.”

“But the FBI has a very close relationship with its British counterparts,” Brennan said. “And so the FBI had visibility into a number of things that were going on involving some individuals who may have had some affiliation with the Trump campaign.”

Attempts to reach Brennan were unsuccessful.

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