(CNN) Former CIA director Leon Panetta said Thursday he believes the intelligence community made every possible attempt to verify unsubstantiated claims that Russia may have compromising information on President-elect Donald Trump.

In an interview on CNN's "Erin Burnett Outfront," Panetta said "I would assume that they made every effort to try to substantiate and corroborate that information."

"So, my sense is that they made the effort, they were unable to do it, but because it was so sensitive, they felt an obligation to present it to the key players," he said.

CNN first reported that the nation's top intelligence chiefs provided both the President and President-elect a two-page written synopsis of the claims, which came from a 35-page report compiled by a former British intelligence operative based on Russian sources. Intelligence agencies appended a two-page summary of the unverified allegations to documents prepared for the briefing on Russian meddling in the 2016 US presidential election.

Multiple US officials briefed on the matter told CNN on Thursday that FBI Director James Comey and Trump had a brief one-on-one conversation at last Friday's intelligence briefing.

Read More