Robert Mueller has confirmed he will testify in open session before two US congressional committees on July 17th.
It comes after the former US Special Counsel was issued with subpoenas by the House of Representatives Judiciary and Intelligence committees.
A joint statement from committee chairmen Jerrold Nadler and Adam Schiff said: "Americans have demanded to hear directly from the special counsel so they can understand what he and his team examined, uncovered, and determined about Russia's attack on our democracy, the Trump campaign's acceptance and use of that help, and President Trump and his associates' obstruction of the investigation into that attack."
Robert Mueller has agreed to testify before Congress pursuant to subpoena.
Russia attacked our democracy to help Trump win. Trump welcomed and used that help. As Mueller said, that should concern every American.
And now, every American will get to hear directly from Mueller.— Adam Schiff (@RepAdamSchiff) June 26, 2019
Both committees have been negotiating with Mr Mueller for two months about his testimony, but the special counsel has been hesitant to testify.
In a letter to Mr Mueller, Mr Nadler and Mr Schiff said: "The American public deserves to hear directly from you about your investigation and conclusions."
Last month, Mr Mueller made a statement about his investigation into Russian interference in the 2016 US presidential campaign.
Mr Trump's campaign was cleared of any attempt to work with Russian meddlers to sway the electorate.
But the report did not make a conclusion about whether or not Mr Trump obstructed justice.
Mr Mueller said: "If we had confidence that the president did not commit a crime we would have said so.
"We did not make a conclusion."
He also told reporters that he could not have charged Mr Trump with an offence while he was sitting as president, because of longstanding US Justice Department protocol.
He said "it would be unfair" to potentially accuse someone of a crime when they could not stand trial to defend themselves."
Responding to the news, Mr Trump simply tweeted: "Presidential Harassment!".
Speaking to MSNBC shortly after Tuesday's announcement, Mr Schiff said Mr Mueller's testimony was a chance for people to have their questions answered about the investigation.
He added: "We never felt it was sufficient to rely simply on a written report or a 10-minute statement without the ability to follow up with questions."
He also said that Mr Mueller's staff would testify in a closed door session with the house intelligence committee.
After the statement in May, Mr Trump said the "case is closed" and repeated his line of "no collusion", calling the investigation the "greatest presidential harassment in history".
The president was investigated for two years over alleged links to Russia which was accused of meddling in the US election in 2016, which saw Mr Trump win the presidency against Hilary Clinton.
