Rep. Devin Nunes, R-Calif., the top Republican on the House Intelligence Committee, said Sunday that special counsel Robert Mueller's Russia investigation team is scraping "the bottom of the barrel" by indicting longtime Trump adviser Roger Stone while also predicting that the "process of discovery" in the case will be a "fascinating" one.

Last week a grand jury indicted Stone on seven counts of lying to Congress, witness tampering, and obstructing a congressional inquiry — stemming from his interview with the House Intelligence Committee in September 2017 as part of its investigation into Russian interference in the 2016 election. Stone has said he will plead not guilty and while he has indicated a willingness to cooperate with Mueller, claims he will not testify against President Trump.

[Related: Roger Stone: FBI raid was 'an attempt to poison the jury pool']

During an interview on Fox News' "Sunday Morning Futures," Nunes said Mueller's prosecutors were "embarrassed" to seek help from GOP investigators who already determined there was no evidence of collusion between the Trump campaign and Russia.

"I think the Mueller investigation is really at the bottom of the barrel when they're looking at people like this because we already found in our report that Roger Stone wasn't colluding with the Russians, which that was the original intent of all this, remember?" Nunes told host Maria Bartiromo.

"Supposedly Trump campaign operatives, so-called, were colluding with Russians," Nunes added. "They must be embarrassed that they actually have to come to House Republicans in order to have us give them the information, the transcripts so that they go and get Roger Stone on a process foul that occurred in 2017 that Roger Stone himself is going to fight. The process of discovery is going to be fascinating in this case and I can't wait to watch it."

Before the Democrats took command of the House, the intelligence panel voted late last year to release Stone's transcript to Mueller's team.

The House Intelligence Committee concluded in April of last year that there was no evidence of Trump-Russia collusion. However, Democrats on the panel, led by now-Chairman Adam Schiff, D-Calif., argued that probe has ended prematurely.