March 22 (UPI) -- Special counsel Robert Mueller submitted a report Friday on his investigation into Russian meddling in the 2016 presidential election to Attorney General William Barr, the Justice Department said.
The contents of the report were not revealed, and it's not clear if or when the details will be released publicly.
Barr sent a letter to congressional leaders notifying them he received the report and will provide a summary to them.
"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," he wrote.
Barr said he plans to consult with Mueller and Deputy Attorney General Rod Rosenstein to determine what information can be released to Congress and the public.
"I remain committed to as much transparency as possible, and I will keep you informed as to the status of my review," he wrote.
A Justice official described the report as "comprehensive" to CNN.
Mueller began his investigation into Russian interference and alleged Trump campaign collusion on May 17, 2017, after an appointment by Rosenstein. To date, Mueller's team has indicted 34 people, including former Trump campaign chairman Paul Manafort, former national security adviser Michael Flynn and a number of Russian GRU officers accused of being involved in a cyberattack against Democratic Party organizations as well as the Clinton campaign.
In December 2019, the Department of Justice said the Mueller probe has cost more than $25 million since it began in spring 2017.
On March 14, the House voted unanimously in favor of a resolution urging Mueller's report to be made public once he completed it. The vote was non-binding and cannot compel the Justice Department to release the report.
"This report must see the light of day, must be available to the American public for a catharsis that will allow us to start with the facts, understand what happened and begin to rebuild the faith of the American people," said Rep. Jim Himes, D-Conn., a senior member of the House intelligence committee.
Earlier this week, President Donald Trump said he believes the report should be made public, despite frequently calling the probe a "hoax" and a "witch hunt."
"I don't mind. I mean, frankly, I told the House, 'If you want, let them see it,'" he said Wednesday when reporters asked him whether the public should be able to read the document.
White House press secretary Sarah Sanders told reporters Friday the next steps for the report are up to Barr.
"We look forward to the process taking its course. The White House has not received or been briefed on the special counsel's report," she said.
Senate Republican leader Mitch McConnell of Kentucky said he hopes Barr will be as "transparent as possible" in what he submits to Congress.
"Many Republicans have long believed that Russia poses a significant threat to American interests," McConnell said. "I hope the special counsel's report will help inform and improve our efforts to protect our democracy.
"Attorney General Barr must not give President Trump, his lawyers or his staff any 'sneak preview' of special counsel Mueller's findings or evidence, and the White House must not be allowed to interfere in decisions about what parts of those findings or evidence are made public," they said.