Special counsel Robert Mueller on Friday delivered his report to Attorney General William Barr on Russia's election meddling and possible collusion with Donald Trump's presidential campaign.
The handoff marks the long-anticipated end of the high-profile and highly guarded Russia probe nearly two years after it began.
Mueller, appointed in May 2017, is no longer formally the special counsel, according to NBC News' Pete Williams.
It remains unclear how much of the report will be made public, but Barr suggested Friday that at least portions of it will be released.
"The Special Counsel has submitted to me today a 'confidential report explaining prosecution or declination decisions' he has reached," Barr wrote in a letter to the leaders of the House and Senate Judiciary committees.
Barr wrote that he intends to consult with Deputy Attorney General Rod Rosenstein and Mueller "to determine what other information from the report can be release to Congress and the public consistent with the law."
"I remain committed to as much transparency as possible, and I will keep you informed as to the status of my review," Barr wrote.
He added: "I am reviewing the report and anticipate that I may be in a position to advise you of the special counsel's principal conclusions as soon as this weekend."
Mueller was appointed by Rosenstein days after Trump abruptly fired former FBI Director James Comey, who had been in charge of the government's investigation into Russian interference in the 2016 presidential election.
The special counsel was authorized to look into Russian meddling and potential "links and/or coordination" with the Trump campaign, as well as "any matters that arose or may arise directly from the investigation." It was later revealed that the special counsel was investigating whether Trump himself obstructed justice.
A spokesman for the special counsel's office did not immediately respond to CNBC's request for comment.
In a tweet, White House press secretary Sarah Huckabee Sanders said, "We look forward to the process taking its course."
The president's lawyers, Jay Sekulow and former New York Mayor Rudy Giuliani, said in a statement: "We're pleased that the Office of Special Counsel has delivered its report to the Attorney General pursuant to the regulations. Attorney General Barr will determine the appropriate next steps."
Mueller's team has lodged indictments against 34 people and three companies. Five people, including Trump's former longtime personal attorney Michael Cohen and former campaign chairman Paul Manafort, have been sentenced to prison.
Trump has denied any wrongdoing related to Mueller's investigation. From its inception, he has decried the probe as a politically motivated "witch hunt."
Former federal prosecutor David Weinstein said it was too soon to draw conclusions about who had and had not been targeted by Mueller.
"Until we read the report, it is only speculation as to why certain people were not indicted and what evidence exists as to the interference, or lack of interference, by the Russian government," Weinstein told CNBC in an email.
"This does not mean that other DOJ components are finished working with the leads that were provided to them by the special counsel's office," Weinstein added.
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