After declaring he wouldn’t, former special counsel Robert Mueller now says he’ll publicly testify before two House committees about his two-and-a-half year long investigation into Russian involvement in Donald Trump’s 2016 presidential election campaign.

He will testify on July 17 before the House Judiciary Committee led by Rep. Jerry Nadler (D-NY) and the House Intelligence Committee headed by Rep. Adam Schiff (D-CA). Mueller was issued subpoenas by both committees and chose to comply with the summons.

Schiff said the committees will question Mueller separately on the same day. He said his committee will question Mueller's staff in a closed session following the public hearing so they can discuss the counterintelligence parts of the investigation.

Mueller will also certainly be asked about his comprehensive report summarizing his investigation into Russia’s efforts to interfere in the 2016 presidential election on behalf of Trump. He will also be asked if Trump tried to derail his investigation and to what extent.

Mueller’s probe ended last March wherein he submitted a 448 page report about his findings to the U.S. Department of Justice (DOJ).

In a joint statement, both Nadler and 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.”

They look forward to hearing his testimony, “as do all Americans.”

In May, Mueller appeared before the media to restate the report’s findings. He also said he wouldn’t speak publicly about the report, which he referred to as his testimony.

Since March, Democrats have contended Mueller’s public testimony is key to understanding the extent of Trump’s potential misconduct both during the election and since he took office.

The subpoenas to Mueller follow weeks of negotiations between Democrats, the special counsel's team and the DOJ.

Mueller Special counsel Robert Mueller (2nd L) leaves after a closed meeting with members of the Senate Judiciary Committee at the Capitol in Washington, D.C., June 21, 2017. Photo: Alex Wong/Getty Images

In their letter to Mueller, Nadler and Schiff said they understand Mueller's concerns about ongoing investigations but they still felt it necessary for Mueller to testify.

"We will work with you to address legitimate concerns about preserving the integrity of your work, but we expect that you will appear before our Committees as scheduled," wrote Nadler and Schiff.

Mueller’s testimonies before both committees controlled by Democrats is bound to be attacked on Twitter and in the media by Trump, who has long complained Mueller’s investigation was a witch hunt.