The conversation between Rep. Jason Chaffetz, R-Utah, and Comey would be the first between the two since Trump dismissed Comey May 9, he said. Chaffetz, a Utah congressman since 2009, said last week that he’ll leave office June 30.

The New York Times reported Friday that Trump called Comey “a nut job” during a White House meeting with Russian Foreign Minister Sergei Lavrov and Ambassador Sergey Kislyak, and that the firing relieved “great pressure” on the president. The Times cited a leaked document summarizing that meeting.

Comey will testify before the Senate Intelligence Committee sometime after Memorial Day, committee leaders have said. Chaffetz disclosed his plan to talk with Comey on ABC’s “This Week” Sunday.

Asked for his reaction to the report about Trump’s comments to the Russian officials, Chaffetz said he doesn’t know what was said but added, “I hope that’s not true.”

Chaffetz said he would like to think that Trump would beat the Russians “over the head” about allegations they interfered with the 2016 U.S. presidential election. National security adviser H. R. McMaster, also on ABC, repeatedly declined to say whether confronting Russia over election hacking was part of the conversation with the Russian delegation.

“The gist of the conversation was that the president feels as if he is hamstrung in his ability to work with Russia to find areas of cooperation because this has been obviously so much in the news,” McMaster said.

Trump’s firing of Comey in the midst of the FBI’s investigation into suspected Russian tampering with the election, possible collusion with the president’s campaign and related matters, touched off a firestorm of criticism from both Democrats and Republicans.

Rep. Elijah Cummings, D-Md., ranking member of the House Oversight Committee, said he hoped Chaffetz would issue subpoenas compelling the White House to release all documentation of Trump’s meeting with the two Russian officials.

“I think documents will help us to ferret out exactly what’s the truth and what’s a lie,” Cummings said.

Chaffetz said he is also chasing documents from Comey who –– after a February meeting with the president –– wrote a file memorandum that may be interpreted as an entreaty from Trump to drop the Russia investigation after the firing of national security adviser Michael Flynn.

“I hope you can let this go,” Trump told Comey, according to the memo, first reported by the New York Times.

“It’s important to remember nobody’s actually seen these documents,” Chaffetz said on Sunday. “There’s been an awful lot written and said about it, but I don’t even know that the Department of Justice has them. Maybe Director Comey has them. I don’t know where they reside. I don’t know if there are documents. But we’re certainly pursuing them.”