US Attorney-General William Barr has defended his handling of special counsel Robert Mueller's report on the Russia investigation, saying the confidential document contains sensitive grand jury material that prevented it from being immediately released to the public.

The statement came as Barr confronts concerns that his four-page letter summarising Mueller's conclusions unduly sanitised the full report in President Donald Trump's favour, including on the key question of whether the President obstructed justice. House Democrats on Thursday approved subpoenas for Mueller's entire report and any exhibits and other underlying evidence that the Justice Department might withhold.

The disparity in length between Barr's letter and Mueller's full report, which totals nearly 400 pages, raises the likelihood of additional significant information that was put forward by the special counsel's office but not immediately shared by the Attorney-General.

In yesterday's statement, Barr defended the decision to release a brief summary letter two days after receiving the report on March 23. He has previously said he did not believe it would be in the public's interest to release the full document in piecemeal or gradual fashion, and that he did not intend for his letter summarising Mueller's "principal conclusions" to be an "exhaustive recounting" of the special counsel's investigation.


Barr is now expected to release the entire report, with redactions, by mid-April.

Barr has said that while Mueller did not establish a criminal conspiracy between Russia and the Trump campaign, the special counsel left open a decision on whether the President had tried to obstruct the Russia investigation. The Mueller team laid out evidence on both sides of the question in a way that neither established a crime nor exonerated Trump, according to Barr's letter.

Barr said he was continuing to work with Mueller's office on redactions to the report so that it could be released to Congress and the public.

- AP