U.S. Attorney General William Barr testifies before a Senate Appropriations Subcommittee hearing on the proposed budget estimates for the Department of Justice in Washington, U.S. April 10, 2019.

Attorney General William Barr will discuss special counsel Robert Mueller's report at a 9:30 a.m. ET press conference on Thursday.

Deputy Attorney General Rod Rosenstein will accompany him, according to NBC News. There was no indication that the report would be released before the press conference.

Mueller submitted the report to the Justice Department late last month. Barr will be releasing a redacted version of the approximately 400-page document, which details Mueller's findings about the Trump campaign and Russian interference in the 2016 election.

The redacted Mueller report on Russian election meddling is expected to be released to the public after Barr's press conference Thursday. Congress is slated to get copies of the report between 11 a.m. and 12 p.m. ET, and it is expected to eventually be posted on the special counsel's Justice Department website.

The special counsel did not establish conspiracy or coordination between the Trump campaign and the Kremlin, Barr wrote in a four page summary released two days after he got the report.

On the question of obstruction, Barr quoted Mueller saying the report "does not conclude that the President committed a crime, [but] it also does not exonerate him."

The final decision on obstruction was left to Barr and Rosenstein They concluded: "The evidence developed during the special counsel's investigation is not sufficient to establish that the president committed an obstruction of justice offense."

Barr had been critical of the probe before Trump nominated him as attorney general. In a memo Barr sent to Justice Department officials in June last year, he explained that he thought the obstruction part of the investigation was "fatally misconceived."

While Trump has celebrated Barr's summary of Mueller's findings, he has also continued to complain that the investigation was a "witch hunt."

The secretive special council probe, which lasted nearly two years, included 19 lawyers and 40 investigators who interviewed hundreds of witnesses, executed nearly 500 search warrants and issued 2,800 subpoenas.

All told, criminal charges were lodged against 35 people and entities, including former Trump campaign chairman Paul Manafort, the president's former personal lawyer Michael Cohen and former national security advisor Michael Flynn.

Barr was confirmed as Trump's attorney general in February. Jeff Sessions, who was attorney general at the time Meuller was appointed special council, was routinely criticized and attacked by Trump for recusing himself from overseeing the investigation due to his contacts with Russian officials.

-CNBC's Kevin Breuninger contributed to this report.