Bartholomew D Sullivan

USA TODAY

WASHINGTON – Paul Manafort, Donald Trump’s former campaign chairman who reportedly received millions from a Russian billionaire to advance the interests of Russian President Vladimir Putin a decade ago, has volunteered to speak with the House intelligence committee, its chairman said Friday.

Chairman Devin Nunes, a California Republican, told reporters the committee was contacted by Manafort’s lawyer with the offer Thursday.

“We thank Mr. Manafort for volunteering and encourage others with knowledge of these issues to voluntarily interview with the committee,” he said.

Rep. Adam Schiff, the ranking Democrat on the committee, claimed in a separate news conference that announcing the Manafort offer was simply an excuse by Nunes to cancel a public committee hearing scheduled for next week featuring members of former President Obama's intelligence team.

Nunes also announced that the committee has requested FBI Director James Comey and National Security Agency director Admiral Michael S. Rogers, who testified in an open session Monday, to return to testify in a closed session.

“It’s necessary to get both of them down here before we can move on,” he said.

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In testimony Monday, Comey revealed that the Trump campaign is the subject of an FBI investigation into whether it coordinated with Russia in the 2016 presidential campaign against Hillary Clinton.

The developments follow a week of dramatic events in which Nunes briefed Trump at the White House after seeing documents that he says identified U.S. citizens in the Trump transition being caught up in incidental surveillance of intelligence agency targets. On Friday, he made a point of noting that he had known of what is referred to as the “unmasking” of those people before he saw documents proving it. He said he doesn’t know who authorized the unmasking or whether there was a legitimate reason for it.

American citizens caught up incidentally when speaking with surveillance targets are not supposed to be identified except under a strict set of exceptions. Democrats say Nunes’ trip to the White House has compromised the investigations the intelligence committee and the FBI are conducting.

Nunes said Manafort can testify at a public hearing or in a closed setting and it was unclear when it might occur.

“We want more people to come forward, and the good thing is that we have continued to have people come forward voluntarily to the committee,” Nunes said, “and I will tell you that will not happen if we tell you who our sources are.” He vowed to “protect the identity of those people at all costs.”

Schiff of California said during his press conference that he would prefer Manafort's testimony be offered in open session and, if necessary, a later closed session can be arranged. He said he had no objection to hearing from Comey and Rogers again in a closed session.

"But as much of this investigation we can do in public, I think we should do," Schiff said.

Schiff said committee Democrats "strongly object" to Nunes' decision to cancel a hearing scheduled for Tuesday with former NSA Director James Clapper, former Acting Attorney General Sally Yates and former CIA director John Brennan. He said the cancellation was an effort to "choke off" information the White House doesn't want the public to hear. Clapper was the first in the intelligence community to say Trump's accusation that his predecessor had wire tapped Trump Tower prior to the November election had no basis.

"We still urge the majority to reconsider, The witnesses have made clear they're still available," Schiff said.

"There must have been a really strong push-back from the White House about the nature" of the now-postponed hearing," Schiff said. "What other explanation can there be?" He said he hoped constituents would contact committee members, especially its Republicans, and urge them to hold the hearing as previously scheduled.

Regarding the briefing of the White House and the documents regarding unmasked Trump associates that only Nunes on the committee has seen, Schiff said he is "concerned that the chairman has been unwilling to rule out that the documents came either from the White House or in coordination with the White House."

With Democrats saying they have lost confidence that Nunes can direct a credible investigation, Schiff was asked if he should be removed as chairman, Schiff said that's Speaker Paul Ryan's call.

"The events of this week are not encouraging," he added..

"One of the profound take-aways of the last couple of days is we really need an independent commission here because the public at the end of the day needs to have confidence that someone has done a thorough investigation," he said.

"The public is discouraged by this week's events," he said, and wants an investigation "unhampered by political pressures and un-interfered with by the White House."

Schiff repeated that it is "abundantly clear" that Trump's wire tap allegations are "pure nonsense." He said that allowing Press Secretary Sean Spicer to claim British intelligence could have had Trump under surveillance harmed relations with Britain.

"To further justify the unjustifiable," Schiff said of the president, "he is now interfering with this investigation."