The US Department of Justice may announce as early as next week that Special Counsel Robert Mueller has given the Attorney-General his report on the federal Russia investigation, according to local media.

Key points: Already, 34 people and three companies have pleaded guilty, been indicted or otherwise swept up in the inquiry, including former Trump advisers

Already, 34 people and three companies have pleaded guilty, been indicted or otherwise swept up in the inquiry, including former Trump advisers When finished, Mr Mueller must submit a confidential report to the Attorney-General explaining his prosecutorial decisions

When finished, Mr Mueller must submit a confidential report to the Attorney-General explaining his prosecutorial decisions The Attorney-General is then required to brief the judiciary committees of Congress about Mr Mueller's report

After the expected announcement, US Attorney-General William Barr will review Mr Mueller's findings and submit his own summary to Congress, CNN reported.

Democrats have been concerned that Mr Barr, who has discretion over what is ultimately made public, will choose to limit disclosure, although the new Attorney-General has said he would seek to make public as much of Mr Mueller's findings as he could.

US President Donald Trump, responding to the CNN report, noted that decision rested with Mr Barr.

"That'll be totally up to the new Attorney-General," Mr Trump told reporters at the White House.

The Mueller probe has spawned other investigations that will continue. ( AP: Susan Walsh )

Mr Mueller is investigating alleged Russian meddling in the 2016 US presidential election and possible collusion by Mr Trump's campaign, as well as possible obstruction of justice by the Republican president.

Mr Trump has denied any collusion and repeatedly slammed the Russia probe as a "witch hunt".

Moscow has also denied any meddling.

So far, 34 individuals and three companies have pleaded guilty, been indicted or otherwise swept up in the inquiry, including several former Trump advisers.

Neither the Justice Department or Mr Mueller wanted to comment about details of the report's submission. ( AP: Manuel Balce Ceneta )

Report will not mark the end of legal scrutiny of Trump

Newly empowered Democrats in the US House of Representatives have said they plan to use Mr Mueller's court filings to build a picture of wrongdoing by Trump advisers that can provide the basis for hearings.

The Mueller probe has also spawned several investigations that are being handled by other offices and will carry on after Mr Mueller's work is done.

Under special counsel regulations, Mr Mueller must submit a confidential report to the Attorney-General explaining his prosecutorial decisions at the conclusion of his work.

The Attorney-General, in turn, is required to inform the judiciary committees of Congress about Mr Mueller's report in the form of "brief notifications, with an outline of the actions and the reasons for them".

How much ultimately becomes public is unclear.

A Justice Department spokeswoman declined to comment on the CNN report, as did a spokesman for Mr Mueller.

Reuters