A full copy of Robert Mueller's report into Russian interference in the 2016 US election will be released by mid-April "if not sooner," the attorney general said.

William Barr said the report is "nearly 400 pages" long, without including appendices, and he hopes to make it public in its entirety with some redactions.

In a letter to Congress the attorney general said: "Everyone will soon be able to read it on their own."

Mr Barr said he was willing to appear before the Senate and House judiciary committees to give evidence about the report on May 1 and May 2.

The redactions will include material intelligence agencies consider could compromise sensitive sources and methods, and secret information given to a grand jury.

Mr Trump has the right to assert executive privilege over some material obtained from the White House.