Former Acting Attorney General Matthew Whitaker disagreed Wednesday with the way former Special Counsel Robert Mueller concluded his nearly two-year-long investigation.

Speaking on "Fox & Friends" ahead of Mueller's highly anticipated congressional testimony, Whitaker said he wants to know why Mueller did not make "prosecution or declination decisions" that were consistent with the special counsel regulations.

"Why, in Part 2, did he just punt and really kind of make it someone else's problem to deal with?" he asked, adding he did not see evidence of a "chargeable" obstruction of justice offense in Mueller's report.

BARR: MUELLER REQUESTED DOJ SEND LETTER LIMITING TESTIMONY TO 'BOUNDARIES' OF HIS REPORT

He said he was "surprised to see" numerous legal experts on television claim that President Trump should have been charged with obstruction, including over the firing of FBI Director James Comey.

"He's allowed to do it. The intent is so important for obstruction and it's just not there," he said.

Whitaker said he did not agree with how the second part of Mueller's report was written, including statements from former FBI deputy Andrew McCabe.

BARR: MUELLER ASKED DOJ TO SEND LETTER LIMITING TESTIMONY TO 'BOUNDARIES' OF REPORT

"I wouldn't give Andy McCabe any credibility as a witness at a trial. I think if you really boil it down, Part 2, I just do not think Bob Mueller did what he should have done under the regulations," said Whitaker, who replaced Jeff Sessions and served from Nov. 2018 until Feb. 2019.

Mueller has already said he will not testify beyond the boundaries of his report into Russian election interference during several hours of hearings before two House panels on Wednesday.

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For Democrats, who have fretted that many Americans never read Mueller's full 448-page report, Mueller's appearances before the House Judiciary and House Intelligence Committees will be an opportunity to again shine the national spotlight on Mueller's lengthy, and deliberately inconclusive, investigation into whether Trump obstructed justice.

Republicans, however, have accused Democrats of "beating a dead hoax." GOP representatives said they wanted to ask when Mueller had determined there was no evidence the Trump team colluded with Russia -- and why Mueller entirely failed to probe apparent surveillance abuses by FBI and DOJ officials in the process.

Fox News' Gregg Re contributed to this report.