David Jackson, and Kevin Johnson

USA TODAY

WASHINGTON — While President Trump encouraged former top aide Michael Flynn to offer testimony to investigators in exchange for immunity from possible prosecution, congressional leaders investigating Russia's interference in the 2016 election signaled Friday that it was too early to consider such an agreement.

"We should first acknowledge what a grave and momentous step it is for a former national security adviser to the president of the United States to ask for immunity from prosecution,'' said California Rep. Adam Schiff, the top Democrat on the House Intelligence Committee. "When the time comes to consider requests for immunity from any witness, we will of course require a detailed proffer of any intended testimony.''

Schiff's statement marked the first public remarks by from any of the leaders of the House and Senate Intelligence committees regarding Flynn's immunity request initially conveyed late Thursday by attorney Robert Kelner.

The California congressman said Flynn's offer would be taken up with leaders of the Senate committee and the Justice Department, where the FBI also is in the midst of a wide-ranging counter-intelligence investigation into Russia's election interference and whether members of Trump's campaign coordinated their efforts with Russian officials. Federal law enforcement officials have engaged in very preliminary discussions about Flynn's prospects for immunity, but no decision has been made, said an official who is not authorized to comment publicly.

Earlier this week, Senate Intelligence Chairman Richard Burr, R-N.C., indicated the panel would pursue testimony from Flynn as part of a roster of 20 witnesses the panel was assembling so far for its inquiry.

"You would think less of us if Gen. Flynn wasn't on that list,'' Burr told reporters.

Earlier Friday, Trump cited Flynn in a tweet denouncing the various Russia-related investigations that now shadow his administration.

"Mike Flynn should ask for immunity in that this is a witch hunt (excuse for big election loss), by media & Dems, of historic proportion!" Trump tweeted.

White House spokesman Sean Spicer said the tweet meant to emphasize that the president had no objection to Flynn's testimony.

"He believes that Mike Flynn should go testify,'' Spicer told reporters Friday. "What he's asking is, 'go testify.' "

Trump's latest missive came just hours after Flynn's attorney issued a tantalizing statement about his client's interest in providing information to congressional and federal investigators.

"Gen. Flynn certainly has a story to tell, and he very much wants to tell it, should the circumstances permit,'' Kelner said, before stating Flynn's desire for immunity.

"No reasonable person, who has the benefit of advice from counsel, would submit to questioning in such a highly politicized, witch-hunt environment without assurances against unfair prosecution,'' Kelner said.

The attorney confirmed that there have been "discussions'' regarding Flynn's possible appearances before the House and Senate Intelligence committees now conducting formal inquires into Russia's attempts to disrupt the American political system.

The FBI is also investigating Russian activity during the 2016 election, including the hacking of Democratic Party officials close to presidential nominee (and Trump opponent) Hillary Clinton. The investigation includes any possible collusion with the Trump campaign, though the president and supporters say they had nothing to do with the Russians.

The Russians also deny wrongdoing.

Dmitry Peskov, a spokesman for Russian President Vladimir Putin, told ABC's Good Morning America that it is "slander" to say that Russia interfered in "domestic affairs of the United States." Peskov said the Kremlin isn't worried about Flynn's potential testimony because there is "no evidence" implicating Russia.

Trump demanded Flynn's resignation last month after learning that the national security adviser misled Vice President Pence and other administration officials about talks he had with Russian ambassador Sergey Kislyak. Flynn initially denied talking about Obama administration sanctions on Russia with Kislyak but later changed his story after evidence to the contrary surfaced.

While lawmakers say they want to hear from Flynn, negotiations are at an early point.

Jack Langer, spokesman for the House Intelligence Chairman Devin Nunes, R-Calif., said a deal for immunity has not been discussed.

Nunes has troubles of his own. Calls have come for the chairman's recusal from Democats, while some Republicans have expressed deep concerns about Nunes' continuing ability to lead.

The wave of criticism came after secretly met at the White House last week to view intelligence reports that he did not share with fellow committee members. The documents, according to the New York Times, were provided by at least two members of the White House National Security Council.

Nunes then conducted a news conference last week in which he said documents showed some members of Trump's presidential transition team had been "incidentally" picked up on surveillance of foreign diplomats. Schiff was scheduled Friday to view what are believed to be the same documents Nunes secretly reviewed last Tuesday.

Trump has since claimed that the information was evidence to support his false claims on March 4 via Twitter that former president Barack Obama had his phones tapped during the campaign, a claim that Obama and FBI Director James Comey have denied.

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