“It was necessary to pull threads.”

Brennan was speaking to the House intelligence committee on the extent of Russia’s meddling in the 2016 elections and possible ties to the Trump campaign, where he was asked about how Moscow recruits sources “wittingly and unwittingly.”

“Frequently, people who go along a treasonous path do not know they are on a treasonous path until it is too late,” Brennan said. "Moreover, the director's admonition that the sharing of any classified information with the Russians should only proceed through intelligence channels, and with significant thought given to ensuring that whatever information is provided would not reveal sources and methods, should serve as a reminder to the White House of the dangers of any impromptu disclosures by the President." Both Trump and numerous Russian officials, including President Vladimir Putin, have repeatedly denied claims of alleged Moscow's collusion with the US president's campaign, as well as of the Kremlin's interference in the 2016 US election. Former CIA Director John Brennan told House Russia investigators Tuesday that Russia “brazenly interfered” in the US elections, including actively contacting members of President Donald Trump’s campaign — but he stopped shy of dubbing it “collusion.”

“I saw interaction that in my mind raised questions of whether it was collusion,” Brennan told Rep. Trey Gowdy, saying that he supported the FBI digging further.
Former CIA Director John Brennan tells the House Intelligence Committee he knew of contacts between Trump associates and Russian officials, but is not sure collusion existed. Brennan said he warned the Russian intelligence service last August against meddling in the U.S. election.