Washington (CNN) An attorney who said he was speaking with President Donald Trump's lawyer Rudy Giuliani reassured Michael Cohen in an April 2018 email that Cohen could "sleep well tonight" because he had "friends in high places," according to a copy of an email obtained by CNN.

Two emails -- both dated April 21, 2018, and among documents provided to Congress by the President's former attorney and fixer -- do not specifically mention a pardon. Cohen, in his closed-door congressional testimony, has provided these emails in an effort to corroborate his claim that a pardon was dangled before he decided to cooperate with federal prosecutors, according to sources familiar with his testimony.

But the attorney who wrote those emails, Robert Costello, told CNN that Cohen's interpretation of events is "utter nonsense." Costello said that Cohen asked him to raise the issue of a pardon with Giuliani.

"Does dangled mean that he (Cohen) raised it and I mentioned it to Giuliani, and Giuliani said the President is not going to discuss pardons with anybody? If that's dangling it, that's dangling it for about 15 seconds," said Costello, who has a four-decade long relationship with Giuliani and was exploring potentially representing Cohen. "The first time I kind of danced around the issue because Michael brought it up with me and I told him, 'Look, this is way too premature. ... But if you want me to bring it up, I will bring it up.' And I did."

A source with knowledge of Cohen's thinking at the time disputes Costello's version of events and insists it was Costello who was pushing his relationship with Giuliani. Another source familiar with the emails said that Trump's legal team was trying to keep Cohen in the fold as a way to keep him quiet, hinting that a pardon could be in the mix at some point.

But Trump's team says it was Cohen and his lawyers who were bringing up a prospect of a pardon.

The two completely contradictory narratives come as congressional committees grapple with the issue of a pardon and Cohen, specifically who initiated the pardon conversations and how far they progressed. Cohen's testimony has sparked a full-blown fight with Republicans accusing Cohen of lying when he said he "never asked for, nor would I accept" a pardon from Trump.

Giuliani told CNN the emails Cohen provided to Congress weren't about pardons.

"That was about Michael Cohen thinking that the President was mad at him," Giuliani told CNN. "I called (Costello) to reassure him that the President was not mad. It wasn't long after the raid and the President felt bad for him."

Lanny Davis, Cohen's attorney and spokesman, told CNN that he couldn't comment on the matter if it involved documents provided to the intelligence committees. "However, as a general matter from my own past experience, it is impossible to deny or try to spin your way out of what documents say. For example, Michael Cohen in his public testimony did not ask anyone to rely on what he was saying alone. He provided documents that speak for themselves to corroborate what he was saying," Davis said.

In the emails obtained by CNN, Costello tells Cohen -- whom Costello says was worried about his relationship with Trump -- that all was well with Trump and that the President was still with him.

"I just spoke to Rudy Giuliani and told him I was on your team," Costello wrote in the first of two emails. "He asked me to tell you that he knows how tough this is on you and your family and he will make (sure) to tell the President. He said thank you for opening this back channel of communication and asked me to keep in touch."

In a follow-up email, Costello told Cohen he had spoken to Giuliani and told Cohen that it was "very very positive."

"There was never a doubt and they are in our corner," Costello wrote. "Rudy said this communication channel must be maintained. He called it crucial and noted how reassured they were that they had someone like me whom Rudy has known for so many years in this role."

"Sleep well tonight, you have friends in high places," Costello ended the email.

It's not known what written response, if any, Cohen had to Costello's emails.

Costello said he first started talking to Cohen after Cohen was raided by the FBI in April 2018, when Cohen was still part of the Trump joint defense agreement. Costello said he was looped in on Cohen's case by his law partner, Jeffrey Citron, who had a previous relationship with Cohen. Citron told Cohen in an email that Costello had experience both with the Southern District of New York and dealing with "highly sensitive matters."

No retainer was signed, according to Costello. At the time, Stephen Ryan was representing Cohen in the exhaustive review of documents seized from Cohen. One source said that Cohen was primarily concerned with a campaign finance violation at that point in the investigation.

Costello said that one reason he spoke to Giuliani was because Cohen was concerned that Trump had soured on him -- or thought that he had soured on Trump -- following a New York Times report that detailed Trump's poor treatment of Cohen. The conversations occurred just days after Giuliani had joined Trump's legal team and Cohen's office and home were searched.

"He wanted to make sure that the boss or the big guy knew that he didn't hate Trump. That he wasn't blaming Trump," Costello said. "There were reports out there that Trump hated Cohen, and that Cohen hated Trump... Michael couldn't say whether Trump hated him. He didn't think so. But he wanted to make sure that Trump knew that he didn't hate Trump."

The morning after Costello's first email was sent, Trump tweeted about Cohen. "Most people will flip if the Government lets them out of trouble, even if...it means lying or making up stories. Sorry, I don't see Michael doing that despite the horrible Witch Hunt and the dishonest media!" the President tweeted.

Costello included a "PS" message in his follow-up email, which was sent after Trump's tweet, noting the "very positive comments about you from the White House. Rudy noted how that followed my chat with him last night."

Cohen testified to Congress that he spoke directly about a pardon with Trump attorney Jay Sekulow, CNN has previously reported, which Sekulow denies. But Cohen said he did not speak about pardons with Giuliani.

Giuliani has previously said he never offered anyone a pardon on behalf of Trump.

Following Cohen's testimony, multiple congressional committees have signaled they plan to investigate the issue of pardons.

"Congress is investigating reports that Trump and his legal team privately dangled pardons to obstruct investigations, including ours," House Intelligence Chairman Adam Schiff of California tweeted on Tuesday.

But Cohen's testimony has also sparked a backlash from Republicans. Ohio Rep. Jim Jordan, the top Republican on the House Oversight Committee, on Wednesday urged Rep. Elijah Cummings, the Democratic chairman of the committee, to join his criminal referral of Cohen to the Justice Department.

"We warned the chairman when you're bringing a guy in front of Congress ... who has a history of lying and specifically lying to Congress, you run this risk," Jordan said last week.

In a letter sent to Cummings Tuesday, Cohen attorney Michael Monico wrote that Cohen's statement "could have been clearer" about the time frame with pardons and when he left the joint defense agreement, but he said the statement was nevertheless still true and Cohen stood by it.

Cummings said in a statement Wednesday he was satisfied with Cohen's clarification and did not intend to take any further action on the matter at this time.

Costello said he had not yet heard from Congress about his conversations with Cohen -- but he expected he might soon.