Attorney General William Barr is reviewing special counsel Robert Mueller's Russia report at the Department of Justice, NBC News reported Saturday.

Barr, who received a copy of the long-awaited report from the special counsel a day earlier, holds the authority to determine which parts of the document will be shared with lawmakers and the public.

In a letter to the leaders of the House and Senate Judiciary committees, Barr said that he might be able to provide them a summary of Mueller's findings as soon as this weekend.

He also suggested that the report, or at least portions of it, would be made public. He wrote that he intended to consult with Mueller and Deputy Attorney General Rod Rosenstein, who oversaw the investigation for much of its duration, "to determine what other information from the report can be released to Congress and the public consistent with the law."

The Justice Department did not immediately respond to CNBC to confirm that Barr was reviewing the report at the DOJ.

Mueller was appointed by Rosenstein in May 2017 to investigate Russian meddling in the 2016 election and whether the Trump campaign and the Kremlin had colluded in that effort. Trump has repeatedly denied any wrongdoing related to Mueller's probe.