And - having told lawmakers previously that his department was scrubbing the report with an eye on a mid-April release - Barr confirmed the Justice Department was on course to make the report public in the next seven days.
"This process is going along very well, and my original timetable of being able to release this by mid-April stands, and I think that, from my standpoint, within a week I will be in a position to release the report to the public," Barr said.
Barr's handling of the nearly 400-page report has roiled Washington in recent weeks, with Democrats pressing to learn the full scope of what the Special Counsel's investigation found.
The House Appropriations Committee is not among those examining Trump, his finances and his foreign contacts, and only one member of the subcommittee that questioned Barr also sits on any of those panels that are.
But Democrats on the House Judiciary Committee had provided members with a list of suggested questions, and as appropriators the lawmakers do have leverage: They could withhold or put conditions on the Justice Department's budget.
"I will consider whatever it takes to get people to see this report," said Representative José Serrano, D, chairman of the Appropriations commerce, justice, science and related agencies subcommittee. "This report is too important to all of us."
Barr's four-page synopsis of Mueller's report said that the Special Counsel did not find that anyone in Trump's campaign conspired with Russia to interfere in the election and that Mueller did not reach a conclusion about whether Trump sought to obstruct justice. Barr wrote that he and Deputy Attorney-General Rod Rosenstein weighed the evidence themselves and determined that they could not make a case that Trump obstructed justice.
Democrats have criticised that bare-bones description, and some on Mueller's team have told associates that they are frustrated with the limited information made available about their work.
Of Mueller's team, Barr conceded: "I suspect that they probably wanted more put out." But he said he was "not interested in putting out summaries or trying to summarise because I think any summary, regardless of who prepares it, not only runs the risk of being under-inclusive or over-inclusive but also would trigger a lot of discussion and analysis that really should have weighed everything coming out at once."
Barr said that Mueller's team "did not play a role in drafting" his letter to Congress, but he added, "We offered to have Bob review it before putting it out, and he declined."
Barr, who received the report on March 22 at the end of Mueller's 22-month investigation, said he rapidly revealed Mueller's conclusions because the public would not tolerate a weeks-long delay in knowing what the investigation had found.
"From a prosecutor's standpoint," he said, "the bottom line is binary, which is charges or no charges." Barr rejected the assertion that he could have quickly made public the summaries the Special Counsel's team prepared because all of the material contains grand-jury information, which by law cannot be released.
Barr could mollify some angst when he releases the report, even though some portions will be redacted. He has told lawmakers that he will keep from public view grand-jury material, information that could reveal intelligence sources and methods, information that could affect ongoing investigations and details that would affect the privacy of people "peripheral" to Mueller's investigation. He said that he will colour-code the redactions and provide "explanatory notes" so people know why various sections of the report are not being disclosed.
Mueller's team, Barr said, was "helping us select the information in the report that falls into those four categories."
He said that Congress will not receive the unredacted report but also that he had promised the Judiciary committees that he would make himself available for interviews and "see if there's a way we can accommodate" requests for more information.
Democrats have urged Barr to make the case to a judge for an exception to the rules that prevent the Justice Department from releasing grand-jury information to Congress, but Barr said he has no plans to do so.
"The chairman of the Judiciary Committee is free to go to court if he feels one of those exceptions is applicable," Barr said. He added, "My intention is not to ask for it at this stage."
House Appropriations Committee Chairwoman Nita Lowey, D, challenged the Attorney-General on how he could have synthesised the nearly 400-page Mueller report into a four-page document so quickly, surmising "your mind must have already been made up."
Barr countered that Rosenstein had long been apprised of the course of Mueller's inquiry, and that he and Rosenstein had met Mueller and his team on March 5 to discuss the wind-down of the investigation.
"We had an inkling of what was coming in our direction," he said.
Barr said that the White House had not reviewed in advance his communications to Congress about the report, but he rebuffed Lowey's attempt to ask whether the White House had seen the report since he sent his summary letter.
"I've said what I'm going to say about the report today," he said.
When Lowey pressed him to say whether Trump had been "factually accurate" about claiming "complete and total exoneration," he similarly declined to engage.
"It's hard to have that discussion without the contents of the report, isn't it? And that's why I suggest we wait until the report is out," Barr told her.
Republicans sought to play down the possibility that the Mueller report might challenge Trump's assertion that he has been exonerated of colluding with Russia, and they asked Barr whether he would now look into whether the conduct of federal law enforcement officials during that investigation had been inappropriate.
Representative Robert Aderholt of Alabama, the subcommittee's top Republican, said it was unfortunate that "so many of the questions here this morning are going toward a 'grassy knoll' conspiracy theory regarding the Mueller report."
He asked whether the Justice Department would look into whether the FBI should have sought a court order to conduct surveillance on former Trump campaign adviser Carter Page.
Barr told lawmakers that the Justice Department's inspector-general would be completing an investigation of how surveillance applications were used in the Russia investigation by "May or June."
