Attorney General William Barr said Thursday that there were 10 potential “episodes” of obstruction of justice by President Donald Trump, but that they didn't amount to illegal activity by the president.

Barr said Trump acted out of "noncorrupt motives" because he was frustrated by the ongoing investigation and media coverage that he felt was hurting his administration.

But Barr acknowledged at a news conference before the public release of special counsel Robert Mueller's report that he disagreed with some of Mueller's legal theories on whether those episodes amounted to obstruction "as a matter of law."

With regard to possible collusion between the Trump campaign and the Russian government, Barr repeatedly insisted that the report did not find "any evidence" of such a conspiracy.

"So that is the bottom line," Barr said. "After nearly two years of investigation, thousands of subpoenas, and hundreds of warrants and witness interviews, the special counsel confirmed that the Russian government sponsored efforts to illegally interfere with the 2016 presidential election but did not find that the Trump campaign or other Americans colluded in those schemes."

Barr also said Trump did not assert executive privilege over the redacted report "in the interests of transparency and full disclosure to the American people." He said most of the redactions were needed "to prevent harm to ongoing matters and to comply with court orders prohibiting the public disclosure of information bearing upon ongoing investigations and criminal cases." Department of Justice attorneys worked with Mueller's office on the redaction process, Barr said.

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Trump's counsel was provided a final version of the redacted report this week, Barr said, adding that the president's attorneys "were not permitted to make, and did not request, any redactions."

Barr's emphasis of "no collusion" was an echo of the president's refrain, repeated over the course of Mueller's nearly two-year investigation. Just after the attorney general's news conference ended, Trump tweeted a meme that played off of the popular TV show "Game of Thrones."

"GAME OVER," the image read.

Asked if he was trying to spin the report in Trump's favor by holding the news conference prior to the report's release, Barr said he was not.

Barr's news conference on the nearly 400-page report on Russian meddling in the 2016 election, whether the Trump campaign colluded with Russian officials and if Trump obstructed justice, preceded the release of a redacted version of Mueller's report. That infuriated critics who said Barr was trying to help Trump by delaying the report's transmission to lawmakers, the media and public.

While Barr stated Thursday that the White House and Trump "fully cooperated with the Special Counsel's investigation" and "took no act that in fact deprive the Special Counsel of the documents and witnesses necessary to complete his investigation," Mueller's report told a slightly different story, lamenting the limited answers Trump himself provided investigators.

Mueller said Trump's written answers to the special counsel demonstrated "the inadequacy of the written format," noting the inability to ask followup questions. Mueller asked again for an in-person interview but was rejected by the president.

"Recognizing that the President would not be interviewed voluntarily, we considered whether to issue a subpoena for his testimony," Mueller wrote. "We viewed the written answers to be inadequate. But at that point, our investigation had made significant progress and had produced substantial evidence for our report. We thus weighed the costs of potentially lengthy constitutional litigation, with resulting delay in finishing our investigation, against the anticipated benefits for our investigation and report."

Mueller's office concluded "that the substantial quantity of information we had obtained from other sources allowed us to draw relevant factual conclusions on intent and credibility, which are often inferred from circumstantial evidence and assessed without direct testimony from the subject of the investigation."

Top Democrats had harsh words for Barr Thursday before his news conference. Senate Minority Leader Chuck Schumer, D-N.Y., called it an "indefensible plan to spin the report."

House Speaker Nancy Pelosi, D-Calif., wrote in a tweet prior that Barr's "partisan behavior has triggered a crisis of independence & impartiality."

"The only way to begin restoring public trust in the handling of the Special Counsel’s investigation is for Special Counsel Mueller himself to provide public testimony in the House and Senate as soon as possible," she continued.

Attorney General Barr’s partisan behavior has triggered a crisis of independence & impartiality. — Nancy Pelosi (@SpeakerPelosi) April 18, 2019

After Barr concluded his news conference, House Judiciary Chairman Jerrold Nadler, D-N.Y., posted on Twitter his formal request for Mueller to testify before his committee before May 23.

It is clear Congress and the American people must hear from Special Counsel Robert Mueller in person to better understand his findings. We are now requesting Mueller to appear before @HouseJudiciary as soon as possible. pic.twitter.com/Mmo6PA4KPt — (((Rep. Nadler))) (@RepJerryNadler) April 18, 2019

"We cannot take Attorney General Barr's word for it," Nadler wrote. "We must read the full Mueller report, and the underlying evidence. This is about transparency and ensuring accountability."

On Wednesday, The New York Times reported that Justice Department officials had held "numerous conversations with White House lawyers" in recent days about Mueller's conclusions. People with knowledge of the discussions told the Times that the talks "aided the president's legal team as it prepares a rebuttal to the report and strategizes for the coming public war over its findings."

The Washington Post, meanwhile, reported Wednesday that the report will be "lightly redacted" and will offer "granular" details into how Trump was suspected of obstructing justice, people familiar with the matter told the outlet.

Trump was tweeting early Thursday ahead of the Mueller report's release, writing, "PRESIDENTIAL HARASSMENT!"

At a Wednesday night news conference, Nadler said the timing of the release was troubling and "wrong."

"The central concern here is that Attorney General Barr is not letting the facts of the report speak for themselves, but is trying to bake in the narrative about the report to the benefit of the White House," he told reporters.