Updated: 10:03 a.m.

Attorney General William Barr held a press conference Thursday morning ahead of releasing a redacted version of Special Counsel Robert Mueller's report on Russia's involvement in the 2016 election. The Justice Department says it will release the 400-page document to Congress at 11 a.m.

The report will give Congress and the public the most information they have been given to date about the findings of the Mueller investigation, which lasted nearly two years. It is unclear how heavily redacted the released document will be. Barr said the redactions will be color-coded based on the reasoning behind each redaction.

Democratic leaders are concerned that Barr is attempting to frame the special counsel's findings himself, rather than allowing the public to independently decipher the report's findings. The attorney general already released a four-page summary of the report in March, emphasizing the conclusion that nobody on the Trump campaign conspired with Russian agents attempting to influence the 2016 election.

Rep. Jerrold Nadler (D-NY), chairman of the House Judiciary Committee, said Wednesday Barr is "taking unprecedented steps to spin" the special counsel's Russia investigation and that he "appears to be waging a media campaign" on Trump's behalf.

Senate Democratic leader Chuck Schumer said "the process is poisoned before the report is even released."

Read More: What To Look For In The Mueller Report

Barr formulated the report's roll-out and briefed the White House on his plans, according to a White House official who was not authorized to discuss the matter publicly. The White House declined to comment on an ABC News report that it had been briefed on the contents of Mueller's report beyond what Barr has made public.

At a later date, the Justice Department also plans to provide a "limited number" of members of Congress and their staff access to a copy of the Mueller report with fewer redactions than the public version, according to a court filing Wednesday.

The Associated Press contributed to this article.