The White House has not yet been briefed on the findings of special counsel Robert Mueller's report, which was submitted to the attorney general Friday concluding a two-year investigation into President Donald Trump and Russia's interference in the 2016 election.

"The next steps are up to Attorney General William Barr, and we look forward to the process taking its course," White House press secretary Sarah Sanders said on Twitter. "The White House has not received or been briefed on the Special Counsel’s report."

No details of Mueller's findings have been released, but Barr said he may be able to brief congressional leaders on the report as soon as this weekend.

Barr also concluded in his letter that Mueller's investigation — relentlessly attacked as improper and a "witch hunt" by Trump — was conducted properly. Barr noted that he was required to inform congressional leaders if Mueller had done anything "inappropriate or unwarranted."

"There were no such instances during the Special Counsel's investigation," the attorney general said, adding that he would determine how much of the report could eventually be released to Congress and the public.

Trump traveled with Sanders and White House counsel, Pat Cipollone, earlier Friday for a fundraising event at his Mar-a-Lago resort in Palm Beach, Florida.

Sen. Lindsey Graham, R-S.C., the chairman of the Senate's Judiciary Committee, was scheduled to be the keynote speaker for the Mar-a-lago event.

Trump's outside lawyers, Rudy Giuliani and Jay Sekulow, issued a statement saying, "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."

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To date, almost three dozen people and three companies have been criminally charged in the sprawling probe, including Trump's former national security adviser Michael Flynn; former campaign chairman Paul Manafort; former political adviser Roger Stone; former personal lawyer Michael Cohen; and numerous Russian nationals. There have been a number of guilty pleas and convictions — but none of the charges have directly accused anyone in Trump's orbit of conspiring with the Russian intelligence operation to help get him elected in 2016.