Three former aides who worked with President Donald Trump during his White House campaign have volunteered to testify before the House Intelligence Committee on any possible ties to Russia and its involvement in the election.

The former aides are campaign manager Paul Manafort, adviser Roger Stone and foreign policy adviser Carter Page, CNN reports.

They will testify Tuesday in a closed session of the committee, Chairman Devin Nunes said Friday.

"We thank Mr. Manafort for volunteering and encourage others to voluntarily interview with the committee," Nunes, the California Republican, said during a news conference.

The Manafort and Stone interviews were offered through their attorneys, while CNN obtained a letter Page wrote to the Intelligence Committee.

Jason Maloni, Manafort's spokesman, said in a statement that his client had agreed to specifically "provide information voluntarily regarding recent allegations about Russian interference in the election."

When asked whether Manafort would agree to be interviewed about his past work as a political consultant in Eastern Europe, Maloni said that the interview would be about Russian interference in the election.

In addition, The Associated Press reported this week that Manafort, before signing up with the Trump campaign, secretly worked for a Russian billionaire and wrote a proposal aimed at benefiting the government in Moscow.

Manafort wrote in a strategy memo obtained by the AP that he would work to "benefit the Putin Government."

He was working as a political consultant for a pro-Russian political party in Ukraine at the time — and Manfort pitched a wide-ranging political influence campaign to aluminum magnate Oleg Deripaska, a close ally of Russian President Vladimir Putin.

The AP report further fueled the controversy about ties between Trump's team and Russia, after FBI Director James Comey on Monday confirmed the agency is investigating whether his campaign associates had contact or coordinated efforts with the Kremlin.

Shortly after Manafort's participation was announced Stone and Page agreed to appear before the House panel, according to the CNN report.

Page stepped down in September amid questions concerning his association with Russians — and reportedly was among several associates who had met with Russian ambassador Sergey Kislyak.

Stone left the campaign in August 2015. The Senate Intelligence Committee has asked him last week to preserve any documents he may have as part of its own Russian investigation.

The attorney for former Trump adviser Roger Stone is informing the committee that his client is willing to talk — and preferably in public — Stone told CNN.

"Mr. Stone deeply resents that several members of your Permanent Select Committee have intimated that he has committed treason in his political, press and social media activities," Stone's attorney said in a letter to the House panel, CNN reports.

"As Mr. Stone has repeatedly stated publicly since these matters have come to light, he is eager to voluntarily appear in open session in front of the Permanent Select Committee on Intelligence without the necessity of a subpoena.

"Mr. Stone is anxious to redress the false and misleading way he has been portrayed by some on the Permanent Select Committee."

In addition, Stone told CNN that he had done nothing wrong.

"I acknowledge I am a hardball player," he said. "I have sharp elbows.

"I always play politics the way it is supposed to be played," he added. "But one thing isn't in my bag of tricks: treason."

Page said in a letter to the committee that he wanted to appear before the committee to "set the record straight."

"I would eagerly welcome the chance to speak with the Committee to help finally set the record straight following the false evidence, illegal activities as well as other lies distributed by certain politically-motivated suspects in coordination with the Obama Administration, which defamed me and other Americans," Page said in the letter that CNN obtained.

Page told CNN that he would prefer to appear at a public hearing — making the same offer the Senate panel.

"My preference is that it be public," Page told CNN, adding he's tired of the "leaks and innuendo."

At his news conference, Nunes told reporters: "We'll allow people to come forward in whatever manner they want to come forward, especially if they're willing to come in freely.

"As for the other names I don't have — there's many names mentioned by several members of Congress and all of you.

"As you said before, we won't get into a neo-McCarthyism era where we start bringing in Americans because they were mentioned in a press story and I'm highly concerned about that."

Nunes also confirmed that he had asked Comey and NSA Director Mike Rogers to return to speak with the Intelligence Committee during a closed session to clear up some questions that linger.

But Nunes also came under fire Friday for canceling a public hearing of the Intelligence Committee that had been set for Monday, enraging top Democratic Rep. Adam Schiff.

"I think this is a serious mistake," Schiff, also of California, told reporters.

He said the committee's hearing this week with Comey demonstrated how important it was that these inquiries be conducted publicly.

"That, of course, is very significant information for the public," Schiff said.

Meanwhile, NSA documents concerning surveillance activities that may or may not have captured names of people involved with the Trump campaign were expected on Friday, but Nunes said it's likely all those document's won't arrive.

"I want to caution I don't expect the entirety of everything we need today, so I would hope by early next week we'll have a better accounting of what the NSA is able to provide us," he said. "I'm telling you that just so you know you don't need to hang out down here, because we won't have any more information on those today."

Earlier this week, Democrats expressed anger after Nunes told reporters and briefed Trump he had seen new information showing that the communications of Trump transition officials were scooped up through monitoring of other targets and improperly spread through intelligence agencies during the final days of the Obama administration.

Democrats were livid that Nunes would meet with Trump before talking to committee members and cited the incident as another reason to question the panel's independence.

Nunes would not disclose the source of the information. But he specifically stated that the new information he received did not support Trump's allegations that former President Barack Obama had ordered a wiretap at Trump Tower.

A member of Trump's transition team after the election, Nunes later apologized to Democrats — saying that the presidential briefing was a judgment call.

"Sometimes you make the right decision, sometimes you make the wrong decision."

The Associated Press contributed to this report.